Apple TV now playing iPhone Lock screen

I believe that this has been posted previously, but not sure if Apple have officially answered the question.

All our television watching is through an Apple TV 4k, using 2 HomePod mini as default speaker output. We use Apple Home to control many things in our house, such as lighting, smoke alarms, water leak sensors and doorbells to name a few. Myself and two daughters are part of our home, my partner is not as she isn’t receiving the invite, although that is a separate issue.

The really annoying problem that myself and two daughters are facing, is that what ever is playing on the Apple TV 4K no matter who started the programme, the three of us have the now playing content and controls on our iPhone lock screens. If someone attempts to play something on our phones like music, it will take over the Apple TV which is incredibly frustrating, I get that actually one can just check and change the source on the iPhone, but this is quite tricky for an 11 year old to remember and quite frankly should be optional to control Apple TV, not the default.

I believe that this is something to do with home though, as my partner doesn’t get the now playing controls on her phone.

I have tried work arounds like turning off handoff and airplay, but they do not appear to have made any difference.