The code I wrote has been working fine if I try to send an IM to users running Skype for Business on Windows. However, for MAC OS users, they receive empty popup (toast message). I get this exception in my code.
{"A 408 (Request Timeout) response was received from the network and the operation failed. See the exception details for more information."}
{ErrorCode=31028,Source=,Reason=The client did not respond to the invitation,component=RTCC/5.0.0.0_UCWA/5.0.0.0 SfBForMac/16.17.65.0000 (Mac OSX 10.13.4),info=No push subscription for target device Microsoft.Rtc.Signaling.DiagnosticHeader }
I tried to troubleshoot the issue with a user. Apparently, he does not receive a popup notification. If he opens the chat window within 30 seconds of receiving the toast message, my code works fine and he receives the IM. If he does not open it in time, I get timeout error on my side.
I debugged the code for Windows users and observed that the flow state changes to Active almost immediately even if the user does not open the chat window. For MAC users, if they ignore the toast message, the flow moves to Terminated and I cannot send them any messages at all.
Any help or work-around will be appreciated.