diff --git a/src/Simplex/Messaging/Agent/Client.hs b/src/Simplex/Messaging/Agent/Client.hs
index dfe538844..96bcd4529 100644
--- a/src/Simplex/Messaging/Agent/Client.hs
+++ b/src/Simplex/Messaging/Agent/Client.hs
@@ -63,7 +63,7 @@ import Simplex.Messaging.Protocol (QueueId, QueueIdsKeys (..), SndPublicVerifyKe
 import qualified Simplex.Messaging.Protocol as SMP
 import Simplex.Messaging.TMap (TMap)
 import qualified Simplex.Messaging.TMap as TM
-import Simplex.Messaging.Util (bshow, liftEitherError, liftError, tryError)
+import Simplex.Messaging.Util (bshow, liftEitherError, liftError, tryError, whenM)
 import Simplex.Messaging.Version
 import System.Timeout (timeout)
 import UnliftIO (async, forConcurrently_)
@@ -79,8 +79,8 @@ data AgentClient = AgentClient
     msgQ :: TBQueue SMPServerTransmission,
     smpServers :: TVar (NonEmpty SMPServer),
     smpClients :: TMap SMPServer SMPClientVar,
-    subscrSrvrs :: TMap SMPServer (Map ConnId RcvQueue),
-    pendingSubscrSrvrs :: TMap SMPServer (Map ConnId RcvQueue),
+    subscrSrvrs :: TMap SMPServer (TMap ConnId RcvQueue),
+    pendingSubscrSrvrs :: TMap SMPServer (TMap ConnId RcvQueue),
     subscrConns :: TMap ConnId SMPServer,
     connMsgsQueued :: TMap ConnId Bool,
     smpQueueMsgQueues :: TMap (ConnId, SMPServer, SMP.SenderId) (TQueue InternalId),
@@ -188,21 +188,24 @@ getSMPServerClient c@AgentClient {smpClients, msgQ} srv =
 
     clientDisconnected :: UnliftIO m -> IO ()
     clientDisconnected u = do
-      removeClientSubs >>= (`forM_` serverDown u)
+      removeClientAndSubs >>= (`forM_` serverDown u)
       logInfo . decodeUtf8 $ "Agent disconnected from " <> showServer srv
 
-    removeClientSubs :: IO (Maybe (Map ConnId RcvQueue))
-    removeClientSubs = atomically $ do
+    removeClientAndSubs :: IO (Maybe (Map ConnId RcvQueue))
+    removeClientAndSubs = atomically $ do
       TM.delete srv smpClients
-      cs_ <- TM.lookupDelete srv $ subscrSrvrs c
-      forM_ cs_ $ \cs -> do
-        modifyTVar' (TM.tVar $ subscrConns c) (`M.withoutKeys` M.keysSet cs)
-        modifyTVar' (TM.tVar $ pendingSubscrSrvrs c) $ addPendingSubs cs
-      return cs_
+      cVar_ <- TM.lookupDelete srv $ subscrSrvrs c
+      forM cVar_ $ \cVar -> do
+        cs <- readTVar cVar
+        modifyTVar' (subscrConns c) (`M.withoutKeys` M.keysSet cs)
+        addPendingSubs cVar cs
+        pure cs
       where
-        addPendingSubs :: Map ConnId RcvQueue -> Map SMPServer (Map ConnId RcvQueue) -> Map SMPServer (Map ConnId RcvQueue)
-        addPendingSubs cs = M.alter (Just . addSubs cs) srv
-        addSubs cs = maybe cs (M.union cs)
+        addPendingSubs cVar cs = do
+          let ps = pendingSubscrSrvrs c
+          TM.lookup srv ps >>= \case
+            Just v -> TM.union cs v
+            _ -> TM.insert srv cVar ps
 
     serverDown :: UnliftIO m -> Map ConnId RcvQueue -> IO ()
     serverDown u cs = unless (M.null cs) $ do
@@ -221,19 +224,26 @@ getSMPServerClient c@AgentClient {smpClients, msgQ} srv =
         reconnectClient `catchError` const loop
 
     reconnectClient :: m ()
-    reconnectClient = do
+    reconnectClient =
       withAgentLock c . withSMP c srv $ \smp -> do
-        subs <- readTVarIO . TM.tVar $ subscrConns c
-        cs <- atomically . TM.lookup srv $ pendingSubscrSrvrs c
-        forConcurrently_ (maybe [] M.toList cs) $ \(connId, rq@RcvQueue {rcvPrivateKey, rcvId}) ->
-          when (isNothing $ M.lookup connId subs) $ do
-            subscribeSMPQueue smp rcvPrivateKey rcvId
-              `catchError` \case
-                e@SMPResponseTimeout -> throwError e
-                e@SMPNetworkError -> throwError e
-                e -> liftIO $ notifySub (ERR $ smpClientError e) connId
-            addSubscription c rq connId
-            liftIO $ notifySub UP connId
+        cs <- atomically $ mapM readTVar =<< TM.lookup srv (pendingSubscrSrvrs c)
+        forConcurrently_ (maybe [] M.toList cs) $ \sub@(connId, _) ->
+          whenM (atomically $ isNothing <$> TM.lookup connId (subscrConns c)) $
+            subscribe_ smp sub `catchError` handleError connId
+      where
+        subscribe_ :: SMPClient -> (ConnId, RcvQueue) -> ExceptT SMPClientError IO ()
+        subscribe_ smp (connId, rq@RcvQueue {rcvPrivateKey, rcvId}) = do
+          subscribeSMPQueue smp rcvPrivateKey rcvId
+          addSubscription c rq connId
+          liftIO $ notifySub UP connId
+
+        handleError :: ConnId -> SMPClientError -> ExceptT SMPClientError IO ()
+        handleError connId = \case
+          e@SMPResponseTimeout -> throwError e
+          e@SMPNetworkError -> throwError e
+          e -> do
+            liftIO $ notifySub (ERR $ smpClientError e) connId
+            atomically $ removePendingSubscription c srv connId
 
     notifySub :: ACommand 'Agent -> ConnId -> IO ()
     notifySub cmd connId = atomically $ writeTBQueue (subQ c) ("", connId, cmd)
@@ -243,10 +253,10 @@ closeAgentClient c = liftIO $ do
   closeSMPServerClients c
   cancelActions $ reconnections c
   cancelActions $ asyncClients c
-  cancelActions . TM.tVar $ smpQueueMsgDeliveries c
+  cancelActions $ smpQueueMsgDeliveries c
 
 closeSMPServerClients :: AgentClient -> IO ()
-closeSMPServerClients c = readTVarIO (TM.tVar $ smpClients c) >>= mapM_ (forkIO . closeClient)
+closeSMPServerClients c = readTVarIO (smpClients c) >>= mapM_ (forkIO . closeClient)
   where
     closeClient smpVar =
       atomically (readTMVar smpVar) >>= \case
@@ -331,7 +341,7 @@ newRcvQueue_ a c srv = do
 
 subscribeQueue :: AgentMonad m => AgentClient -> RcvQueue -> ConnId -> m ()
 subscribeQueue c rq@RcvQueue {server, rcvPrivateKey, rcvId} connId = do
-  addPendingSubscription c rq connId
+  atomically $ addPendingSubscription c rq connId
   withLogSMP c server rcvId "SUB" $ \smp -> do
     liftIO (runExceptT $ subscribeSMPQueue smp rcvPrivateKey rcvId) >>= \case
       Left e -> do
@@ -343,17 +353,17 @@ subscribeQueue c rq@RcvQueue {server, rcvPrivateKey, rcvId} connId = do
 addSubscription :: MonadUnliftIO m => AgentClient -> RcvQueue -> ConnId -> m ()
 addSubscription c rq@RcvQueue {server} connId = atomically $ do
   TM.insert connId server $ subscrConns c
-  addSubs_ rq connId $ subscrSrvrs c
+  addSubs_ (subscrSrvrs c) rq connId
   removePendingSubscription c server connId
 
-addPendingSubscription :: MonadUnliftIO m => AgentClient -> RcvQueue -> ConnId -> m ()
-addPendingSubscription c rq connId =
-  atomically . addSubs_ rq connId $ pendingSubscrSrvrs c
+addPendingSubscription :: AgentClient -> RcvQueue -> ConnId -> STM ()
+addPendingSubscription = addSubs_ . pendingSubscrSrvrs
 
-addSubs_ :: RcvQueue -> ConnId -> TMap SMPServer (Map ConnId RcvQueue) -> STM ()
-addSubs_ rq@RcvQueue {server} connId = TM.alter (Just . addSub) server
-  where
-    addSub = maybe (M.singleton connId rq) (M.insert connId rq)
+addSubs_ :: TMap SMPServer (TMap ConnId RcvQueue) -> RcvQueue -> ConnId -> STM ()
+addSubs_ ss rq@RcvQueue {server} connId =
+  TM.lookup server ss >>= \case
+    Just m -> TM.insert connId rq m
+    _ -> TM.singleton connId rq >>= \m -> TM.insert server m ss
 
 removeSubscription :: MonadUnliftIO m => AgentClient -> ConnId -> m ()
 removeSubscription c@AgentClient {subscrConns} connId = atomically $ do
@@ -363,13 +373,9 @@ removeSubscription c@AgentClient {subscrConns} connId = atomically $ do
 removePendingSubscription :: AgentClient -> SMPServer -> ConnId -> STM ()
 removePendingSubscription = removeSubs_ . pendingSubscrSrvrs
 
-removeSubs_ :: TMap SMPServer (Map ConnId RcvQueue) -> SMPServer -> ConnId -> STM ()
-removeSubs_ ss server connId = TM.update delSub server ss
-  where
-    delSub :: Map ConnId RcvQueue -> Maybe (Map ConnId RcvQueue)
-    delSub cs =
-      let cs' = M.delete connId cs
-       in if M.null cs' then Nothing else Just cs'
+removeSubs_ :: TMap SMPServer (TMap ConnId RcvQueue) -> SMPServer -> ConnId -> STM ()
+removeSubs_ ss server connId =
+  TM.lookup server ss >>= mapM_ (TM.delete connId)
 
 logServer :: AgentMonad m => ByteString -> AgentClient -> SMPServer -> QueueId -> ByteString -> m ()
 logServer dir AgentClient {clientId} srv qId cmdStr =
diff --git a/src/Simplex/Messaging/Server.hs b/src/Simplex/Messaging/Server.hs
index 102830353..938ba9aa1 100644
--- a/src/Simplex/Messaging/Server.hs
+++ b/src/Simplex/Messaging/Server.hs
@@ -137,7 +137,7 @@ runClientTransport th@THandle {sessionId} = do
 clientDisconnected :: (MonadUnliftIO m, MonadReader Env m) => Client -> m ()
 clientDisconnected c@Client {subscriptions, connected} = do
   atomically $ writeTVar connected False
-  subs <- readTVarIO $ TM.tVar subscriptions
+  subs <- readTVarIO subscriptions
   mapM_ cancelSub subs
   cs <- asks $ subscribers . server
   atomically . mapM_ (\rId -> TM.update deleteCurrentClient rId cs) $ M.keys subs
diff --git a/src/Simplex/Messaging/Server/Env/STM.hs b/src/Simplex/Messaging/Server/Env/STM.hs
index 5187c0d73..3c4599a97 100644
--- a/src/Simplex/Messaging/Server/Env/STM.hs
+++ b/src/Simplex/Messaging/Server/Env/STM.hs
@@ -114,9 +114,9 @@ newEnv config@ServerConfig {caCertificateFile, certificateFile, privateKeyFile}
     restoreQueues QueueStore {queues, senders, notifiers} s = do
       (qs, s') <- liftIO $ readWriteStoreLog s
       atomically $ do
-        writeTVar (TM.tVar queues) =<< mapM newTVar qs
-        writeTVar (TM.tVar senders) $ M.foldr' addSender M.empty qs
-        writeTVar (TM.tVar notifiers) $ M.foldr' addNotifier M.empty qs
+        writeTVar queues =<< mapM newTVar qs
+        writeTVar senders $ M.foldr' addSender M.empty qs
+        writeTVar notifiers $ M.foldr' addNotifier M.empty qs
       pure s'
     addSender :: QueueRec -> Map SenderId RecipientId -> Map SenderId RecipientId
     addSender q = M.insert (senderId q) (recipientId q)
diff --git a/src/Simplex/Messaging/TMap.hs b/src/Simplex/Messaging/TMap.hs
index 012adde4b..a6584903e 100644
--- a/src/Simplex/Messaging/TMap.hs
+++ b/src/Simplex/Messaging/TMap.hs
@@ -1,6 +1,7 @@
 module Simplex.Messaging.TMap
-  ( TMap (..),
+  ( TMap,
     empty,
+    singleton,
     Simplex.Messaging.TMap.lookup,
     member,
     insert,
@@ -10,6 +11,7 @@ module Simplex.Messaging.TMap
     adjust,
     update,
     alter,
+    union,
   )
 where
 
@@ -17,44 +19,52 @@ import Control.Concurrent.STM
 import Data.Map.Strict (Map)
 import qualified Data.Map.Strict as M
 
-newtype TMap k a = TMap {tVar :: TVar (Map k a)}
+type TMap k a = TVar (Map k a)
 
 empty :: STM (TMap k a)
-empty = TMap <$> newTVar M.empty
+empty = newTVar M.empty
 {-# INLINE empty #-}
 
+singleton :: k -> a -> STM (TMap k a)
+singleton k v = newTVar $ M.singleton k v
+{-# INLINE singleton #-}
+
 lookup :: Ord k => k -> TMap k a -> STM (Maybe a)
-lookup k (TMap m) = M.lookup k <$> readTVar m
+lookup k m = M.lookup k <$> readTVar m
 {-# INLINE lookup #-}
 
 member :: Ord k => k -> TMap k a -> STM Bool
-member k (TMap m) = M.member k <$> readTVar m
+member k m = M.member k <$> readTVar m
 {-# INLINE member #-}
 
 insert :: Ord k => k -> a -> TMap k a -> STM ()
-insert k v (TMap m) = modifyTVar' m $ M.insert k v
+insert k v m = modifyTVar' m $ M.insert k v
 {-# INLINE insert #-}
 
 delete :: Ord k => k -> TMap k a -> STM ()
-delete k (TMap m) = modifyTVar' m $ M.delete k
+delete k m = modifyTVar' m $ M.delete k
 {-# INLINE delete #-}
 
 lookupInsert :: Ord k => k -> a -> TMap k a -> STM (Maybe a)
-lookupInsert k v (TMap m) = stateTVar m $ \mv -> (M.lookup k mv, M.insert k v mv)
+lookupInsert k v m = stateTVar m $ \mv -> (M.lookup k mv, M.insert k v mv)
 {-# INLINE lookupInsert #-}
 
 lookupDelete :: Ord k => k -> TMap k a -> STM (Maybe a)
-lookupDelete k (TMap m) = stateTVar m $ \mv -> (M.lookup k mv, M.delete k mv)
+lookupDelete k m = stateTVar m $ \mv -> (M.lookup k mv, M.delete k mv)
 {-# INLINE lookupDelete #-}
 
 adjust :: Ord k => (a -> a) -> k -> TMap k a -> STM ()
-adjust f k (TMap m) = modifyTVar' m $ M.adjust f k
+adjust f k m = modifyTVar' m $ M.adjust f k
 {-# INLINE adjust #-}
 
 update :: Ord k => (a -> Maybe a) -> k -> TMap k a -> STM ()
-update f k (TMap m) = modifyTVar' m $ M.update f k
+update f k m = modifyTVar' m $ M.update f k
 {-# INLINE update #-}
 
 alter :: Ord k => (Maybe a -> Maybe a) -> k -> TMap k a -> STM ()
-alter f k (TMap m) = modifyTVar' m $ M.alter f k
+alter f k m = modifyTVar' m $ M.alter f k
 {-# INLINE alter #-}
+
+union :: Ord k => Map k a -> TMap k a -> STM ()
+union m' m = modifyTVar' m $ M.union m'
+{-# INLINE union #-}