Adidas training app on Apple TV4k

I am running the Adidas training App on a brand new Apple TV 4k.

In order to use the training plans the app asks me to connect to the Adidas training app that is running on my phone or Ipad.

It will not connect and so the training plans are not working.

Sadly the support form adidas/runtastic is very basic, just bots sending the same message over and over.

I made sure both Apps (on Phone and Apple TV) are the latest version (Using an old IPhone SE with OS14).

I made sure both Apps are logged into the same account.

I restarted both Apps, just like Adidas advises on its site.

I tried the same with the App running on my IPad (IPad Pro, OS14) instead of my IPhone, to no effect.

Has anyone else that problem too?

Thanks for your help :-)