Happened to me too. Hope it gets fixed again. Things I tried:
Emergency reset (My flow, in the 3-dot menue)
Reinstalling Opera GX on the Computer and Phone
Typing connection code manually
Resetting Opera GX's settings
Acivating/Deactivaing acount syncing
. . .
Screen:
Bild_2024-09-09_122011160.png
Hope it gets fixed again