In my case it is working eight days for now. Of course after removing all GMS and GPay cache and data and hiding GMS and GPay in Magisk Hide. Before this I tried many times with stopping update of GMS on elder versions etc. and issue went back. Now it seems like a permament solution. In the meantime I upgraded Magisk from 18.2 to 19.0 and my GMS has been autoupdated from 16.0.86 to 16.0.89 and GPay still works. I added six cards and all of them works like a charm.
Do you recall when doing any of this if you had WiFi turned off? Because in my case, this was the deciding factor.