Belarus tax info in App Store Connect — "Try again later" error for 10+ days

For more than 10 days, I haven't been able to add tax information for Belarus in App Store Connect (Business section).

Every time I try to enter my details, I get the same error:

"Unable to process the request at this time. Please try again later."

Because of this:

I have no access to the information entry field

I can't submit my app for review

I can't upload or submit any new app

I tried different variations of my tax number — nothing helps. The problem is not on my side.

Has anyone else faced this? How did you fix it? Support is silent, and my deadlines are burning.

Thanks.