I just managed to connect my Adobe Analytics account to Google Sheets via the Supermetrics add-on, but when I try to connect AA to GDS im just stuck in a loading screen after entering my credentials.
I've tried to refresh the page but the same loading screen opens up, even though i have not entered my credentials for a second time.
First, if you haven't seen this article yet, take a look to see if that has any additional steps that user hasn't done yet:
It also mentions a username/shared secret that can be used instead of the normal login that some people have more success with (just depends on if that user can get the shared secret, not all users have permissions to do this).
Second, the Adobe Analytics permissions scheme can be rather granular with users being able to see the presence of but not be able to open/access some reports, or fields inside the report. I spoke with the dev as others have been running into similar issues, and it seems that if that user can see but not access any report in the potential list of things the connector could pull data for, it bounces the login.
Third possibility has to do with the migration from my.omniture.com to Adobe Experience Cloud/Adobe.io. If the company is in the middle of this migration, things can get weird as the permissions schemas changed in the newer system. The connector is supposed to have some handling for this, but it's not 100% if the user/account is mid-migration. I don't know if this applies to you at all, but I wanted to mention it as a factor.
Please check those things to see if they are factors. If not, then let us know so we can investigate further.