Partner Center: creating a payout profile always fails with "technical problem" (paymentcentralnext)

Individual Microsoft Store developer, Individual account type, personal Microsoft Account (MSA), region China. Seller ID 96339890.

I need a payout profile to publish a paid subscription add-on.

Problem: from Partner Center > Account settings > Payout and tax profile assignment, creating a bank payout profile (Electronic bank transfer, China) redirects to paymentcentralnext.microsoft.com which always shows "Sorry, we have a technical problem".

Correlation/Reference IDs from three attempts:

• 1dc1dae6-1566-4190-99e3-6f0d62a86d7e / dfe2b258-8911-4f0c-8051-c1b90ae65ec7
• • 3db11667-e9b7-49b7-b202-9db249bafcb6 / 087e43ed-0627-42a7-9cd7-162822872308
  • • e77f3dee-6273-4355-9ffd-8f7e95f4542c / 1d6c8333-921b-4ffb-b9cb-32518ec72b59
  • Related: the tax form at taxprofile.pmp.microsoft.com first failed with "unable to authorize you based on the credentials you provided". After retries the W-8BEN was submitted - S&P Global shows "Certified" and "pending Microsoft validation" (ref 66281b10-64a3-43a8-a9d1-c338d907a174) - but Partner Center still showed the tax form as incomplete/None.
• Also: the Dev Center support portal (the "MSA users click here" link) cannot be used at all - it bounces between login.microsoftonline.com/<tenant>/oauth2/v2.0/authorize and login.microsoftonline.com/organizations/oauth2/v2.0/authorize, i.e. it requires an Entra ID work/school account and rejects the personal MSA. That is why I am posting here.

Tried: Edge/Chrome, InPrivate, third-party cookies and pop-ups allowed, cleared microsoft.com cookies, correct entry point, more than 48h wait, many retries. No luck.

Can a Microsoft engineer check the backend for this account? Happy to provide any additional details through a private channel.