Partner Center: "Payout and tax profiles" always fails, so we can't submit a paid add-on

Our app is published in the Microsoft Store (private audience). Our subscription add-on won't submit: "You need to update your tax and payout information before you can charge money."

But Account settings → Payout and tax → Payout and tax profiles always shows "We couldn't complete your request. Please try again". This has happened since 7 October 2026, in Chrome and in a clean Edge InPrivate window, signed in as the account owner (a Microsoft account, not Entra ID). The older payout page says "Access restricted… you don't have permission" (correlation ID 91efbedc-7d0c-41f6-afbe-c0c104b4cec7).

Is a Microsoft-account owner allowed to set up payout and tax, or must it be done by an Entra ID global admin linked to the Partner Center account? We have a support case open (2610080040001094).