Making a Google Voice call has been causing my phone to drop it's LTE connection.

This problem only started happening sometime last year, or in late 2019. Beforehand, I could make calls with Google Voice while connected only to LTE (no WiFi) and it would work just as a normal call.

Now, when I make a GV call, the LTE icon disappears, and there is no connection or ringing or anything but silence. The LTE icon returns only once I end the call.

I don't know what it means that the icon goes away. Maybe that Verizon wont let me connect a Google call over their LTE network, or my sim card is disabling for some reason?....I have looked all in the settings of the phone and Google Voice for something having to do with turning off the mobile data, or only using it over WiFi, but I seem to have everything set to /prefer/ WiFi, but still use mobile data.

A Google Voice "product expert" told me he was able to connect a GV call over LTE just fine, so it isn't a Verizon policy, is it? I have been unable to use my main telephone number outside of WiFi and it is incredibly frustrating. Any help would be greatly appreciated.

I am using a Samsung A20.