Signal good, phone connected, still always obtaining signature!

Ok, trial running out fast and still can’t use the Garmin, worked once, every other time the screen stays on ‘obtaining signature, login via phone, done that numerous times, nothing, any ideas? Rapidly losing he will to live! Typing this while riding, s obviously logged on, even tried mobile data on and off on phone, can’t think of much else.

Another40 mins, given up, back to Zwift ‘just ride’…