Apple TV asking for iCloud account when I'm signed in
I am running Apple TV HD, iOS 14.7 and OS 10.15. Everything is fine with MacBook and phone but Apple TV won't recognise that I'm signed in to iCloud when I want to use Homekit, it says ""AirPlay 2 and HomeKit require an iCloud account" even though I am signed in with the same ID as on my other two devices. I cannot get Apple TV to ask for a verification code, according to the device info on my iCloud account. I have tried the "work around" of adding the verification code generated from my phone to the end of my password, but no luck.
Is there a way of solving this?