Bluetooth issues on iPhone 6 plus

Is anyone having any kind of Bluetooth issues on the 6 plus?
I'm having issues with my car connectivity. Got the 14 Altima with navi. I connect the phone and after a few days the service field says "no network" where att usually is. Car is still connected to the phone as per cars display and as per iPhone itself. But calls don't come in or come out. Exchanged the phone at Apple store. Same thing. First few days it's good then the same problem. Fixed by resetting settings on the phone...but again only for a few days. Anyone else can relate?

 

Yeah I've done that. Next step is to go to the dealer and have them do a hard reset. But I doubt that'll work. I see a lot of complaints about the same issue with other cars. This is unreal. I can't believe apple has botched so much with this phone and software. Wouldn't have happened if Jobs was still around.