Hi Michael,
The Microsoft support engineer will help to solve the problem from backend. Sometime delay might be expected. Your patience is greatly appreciated. Thank you for understanding and support.
Any of the following can result in a sync group being stuck in the processing state.
a)The client agent is offline.
Be sure that the client agent is online then try again.
b)The client agent is uninstalled or missing.
If the client agent is uninstalled or otherwise missing:
1)Remove agent XML file from the SQL Data Sync (Preview) installation folder if the file exists.
2)Install the agent on same/another on-premise computer, submit the agent key from the portal generated for the agent thats showing offline.
c)The SQL Data Sync (Preview) service is stopped.
1)In the Start menu, search on Services.
2)Click Services in the Programs section of the search results.
3)Find the SQL Data Sync (Preview) service.
4)If the service status is Stopped right-click the service name and select Start from the dropdown menu.
Reference :
http://msdn.microsoft.com/en-us/library/azure/hh667321.aspx#ProcessingError
Regards,