diff --git a/internal/msggateway/client.go b/internal/msggateway/client.go
index af96e7d460..6e31751dc8 100644
--- a/internal/msggateway/client.go
+++ b/internal/msggateway/client.go
@@ -446,6 +446,8 @@ func (c *Client) handlerTextMessage(b []byte) error {
 		if err != nil {
 			return err
 		}
+		c.w.Lock()
+		defer c.w.Unlock()
 		if err := c.conn.SetWriteDeadline(writeWait); err != nil {
 			return err
 		}