login bug

I have a problem with the login console. Each time I turn on the server, I have to restart it for it to work. Someone would have a solution

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Code:

  private string BuildServersPacket(string username, int sessionId, bool ignoreUserName)
        {
            string channelpacket =
                CommunicationServiceClient.Instance.RetrieveRegisteredWorldServers(username, sessionId, ignoreUserName);

            if (channelpacket == null || !channelpacket.Contains(':'))
            {
                Logger.Debug(
                    "Could not retrieve Worldserver groups. Please make sure they've already been registered.");
                _session.SendPacket($"fail {Language.Instance.GetMessageFromKey("NO_WORLDSERVERS")}");
            }

            return channelpacket;
        }