ios15.1 bluetooth dropping devices

I have a Iphone 12 pro max, recently updated to iOS15.1, since doing this my iphone will drop bluetooth connections. I have done a hard restart, reset network connections, forget all bluetooth devices and deleted the iPhone profile form the devices i am trying to connect too and repaired the devices. Nothing has changed, frustrated as i use a hands free connection in my car for work and it is constantly dropping calls or switching audio to the phone.