Hey y'all as I was setting up my Stadia account I was offered a free trial of pro but accidentally declined it now I can find where to get it anywhere. Any help would be much appreciated!
As far as I know, this is not solvable using the Stadia app. I would recommend you to contact the Support chat. Maybe they are accommodating and help you.
Support Chat: https://support.google.com/stadia/contact/stadia_chat