diff --git a/proxy/lib/snowflake.go b/proxy/lib/snowflake.go
index aa9175f..0e2517e 100644
--- a/proxy/lib/snowflake.go
+++ b/proxy/lib/snowflake.go
@@ -485,6 +485,10 @@ func (sf *SnowflakeProxy) makePeerConnectionFromOffer(
 			}
 		})
 		dc.OnClose(func() {
+			// Make sure that the `Write()`s are not blocked any more.
+			dc.OnBufferedAmountLow(func() {})
+			close(conn.sendMoreCh)
+
 			conn.lock.Lock()
 			defer conn.lock.Unlock()
 			log.Printf("Data Channel %s-%d close\n", dc.Label(), dc.ID())
diff --git a/proxy/lib/webrtcconn.go b/proxy/lib/webrtcconn.go
index f92e87b..f849bfa 100644
--- a/proxy/lib/webrtcconn.go
+++ b/proxy/lib/webrtcconn.go
@@ -33,8 +33,6 @@ type webRTCConn struct {
 	lock sync.Mutex // Synchronization for DataChannel destruction
 	once sync.Once  // Synchronization for PeerConnection destruction
 
-	isClosing bool
-
 	inactivityTimeout time.Duration
 	activity          chan struct{}
 	sendMoreCh        chan struct{}
@@ -45,7 +43,6 @@ type webRTCConn struct {
 
 func newWebRTCConn(pc *webrtc.PeerConnection, dc *webrtc.DataChannel, pr *io.PipeReader, bytesLogger bytesLogger) *webRTCConn {
 	conn := &webRTCConn{pc: pc, dc: dc, pr: pr, bytesLogger: bytesLogger}
-	conn.isClosing = false
 	conn.activity = make(chan struct{}, 100)
 	conn.sendMoreCh = make(chan struct{}, 1)
 	conn.inactivityTimeout = 30 * time.Second
@@ -89,7 +86,7 @@ func (c *webRTCConn) Write(b []byte) (int, error) {
 	defer c.lock.Unlock()
 	if c.dc != nil {
 		_ = c.dc.Send(b)
-		if !c.isClosing && c.dc.BufferedAmount() >= maxBufferedAmount {
+		if c.dc.BufferedAmount() >= maxBufferedAmount {
 			<-c.sendMoreCh
 		}
 	}
@@ -97,11 +94,6 @@ func (c *webRTCConn) Write(b []byte) (int, error) {
 }
 
 func (c *webRTCConn) Close() (err error) {
-	c.isClosing = true
-	select {
-	case c.sendMoreCh <- struct{}{}:
-	default:
-	}
 	c.once.Do(func() {
 		c.cancelTimeoutLoop()
 		err = errors.Join(c.pr.Close(), c.pc.Close())