revvl v +5g bluetooth

I've found my REVVL V+5G refuses to connect to any of my cars, 2 Fords and a Toyota.  Constantly connects and disconnects - with repeated Bluetooth App (in the phone) crashing.  I have taken it to 4 different T-mobile stores and in each one, they tinker around, make sure the software updates are all done, and then do a factory reset - then hand it back to me, telling me it's fixed and should be working fine in about an hour . . . . it never works.  I then have to spend a couple hours reloading all my 2 factor authentication profiles back into the phone, since the Google backup/restore never keeps them functional.  Found it also has trouble staying connected to a bluetooth speaker I like using on the back deck.  We have 4 iPhones in the family (including my work issued phone), and they all work without any of these issues with all the cars and the speaker.

The last 2 times I took it to the stores, I asked for a replacement, and they refuse - claiming that the factory reset should fix it, and there’s no defect.