diff --git a/v2rayN/ServiceLib/Models/SingboxConfig.cs b/v2rayN/ServiceLib/Models/SingboxConfig.cs
index 9146ee91..bfa644a8 100644
--- a/v2rayN/ServiceLib/Models/SingboxConfig.cs
+++ b/v2rayN/ServiceLib/Models/SingboxConfig.cs
@@ -154,7 +154,7 @@ public class Endpoints4Sbox : BaseServer4Sbox
     public int? mtu { get; set; }
     public List<string> address { get; set; }
     public string private_key { get; set; }
-    public int listen_port { get; set; }
+    public int? listen_port { get; set; }
     public string? udp_timeout { get; set; }
     public int? workers { get; set; }
     public List<Peer4Sbox> peers { get; set; }
diff --git a/v2rayN/ServiceLib/Services/CoreConfig/CoreConfigSingboxService.cs b/v2rayN/ServiceLib/Services/CoreConfig/CoreConfigSingboxService.cs
index a9990ffb..0d52c683 100644
--- a/v2rayN/ServiceLib/Services/CoreConfig/CoreConfigSingboxService.cs
+++ b/v2rayN/ServiceLib/Services/CoreConfig/CoreConfigSingboxService.cs
@@ -785,7 +785,6 @@ public class CoreConfigSingboxService
         try
         {
             endpoint.address = Utils.String2List(node.RequestHost);
-            endpoint.listen_port = Utils.GetFreePort();
             endpoint.type = Global.ProtocolTypes[node.ConfigType];
 
             if (Utils.IsDomain(node.Address))