Just bought Cubase 12 upgrade. Refuses to authorise

Hi all. Bought upgrade from Cubase 11 pro. Downloaded and installed ok but caught in a loop between these 2 windows. Signing in with correct name and password but just keeps going back to try again. Tried Chrome and Microsoft Edge. Tried rebooting of course. Tried signing out of My Steinberg too. Also disabled antivirus and antimalware. Any help? Eddie

OK, tried the old “Run this program as administrator” trick and at least it got me to activation page. Clicked and it said authorised. Now to try opening Cubase 12 for the first time.

Excellent. Only took 3 and a half hours of hassle but I eventually have a Cubase 12 that opens. Loaded a complex existing song with full band and a string quartet and it played back fine. Got alarmingly long list of plugins that seem dead but will investigate. Izotope listed but the plugins are there so probably a blacklist issue.