Ultra 2 Watch and older apps from iPhone.

Hi all.

I am trying to add Gogogate2 garageopener app to my Ultra 2 watch. The app works excellent on iPhone 15 pro but when I open it up in Ultra 2 it just shows the spinning wheel and the code for the garageopener. The app has been erased and reinstalled but in vain. The opener and its app is no longer supported by the manufacturer...

Any suggestions?

Thank you

Jesper