Also not working, glad to know it's not just me. Mine stopped synching on 7/26. I updated system software on Android on 7/27.
Windows 10 - Message +, v 22.214.171.124. Also tried lastest Verizon Messages and same problem.
Messages go through but don't show up on phone and messages from phone don't show up on comptuer.
Android - Message+ 6.8.5 on Samsung Galazy 9+
What's odd is that I also have Message+ on an iPad and I can see everything on it.
Please fix it asap.