Selected user account does not exist in tenant 'Microsoft Services' and cannot access the application, ---- Unable to sign in with my Personal Microsoft Account (MSA) that owns the Azure Sponsorship; my work account lacks subscription/billing access, the

Unable to sign in with my Personal Microsoft Account (MSA) that owns the Azure Sponsorship; my work account lacks subscription/billing access, the original Entra ID user was deleted, the MSA is now detached and cannot be re-added due to a verified domain conflict, leaving Azure for Startups credits orphaned and blocking login, billing access, and even support ticket creation (AADSTS160021 / AADSTS50020).

I was approved for an Azure for Startups $1,000 credit, but the credit was never redeemed.

The startup application and credit approval were done using a Personal Microsoft Account (MSA).
Before redeeming the credit, I proceeded to properly set up Microsoft Entra ID for my company tenant (clarigenai.com) and cleaned up temporary/guest users created during onboarding.

After this, the system entered a broken state:

The MSA that owns the Azure for Startups credit can no longer sign in

Azure Portal sign-in fails with AADSTS160021 and AADSTS50020

The portal says “You don’t have a billing account to redeem the credit”

Cost Management shows the subscription as “not supported / unauthorized”

The credit is visible in Azure for Startups, but not attached to any billing account or subscription

At this point:

I cannot log in using the original MSA

I cannot attach or redeem the startup credit

I cannot invite the MSA as an external user

I cannot create Azure support tickets, because ticket creation itself requires the missing MSA session or billing permissions

This leaves me completely blocked — I am unable to manage billing, redeem credits, or even raise a support request through the Azure Portal.

What is needed

This issue cannot be resolved via self-service.

I need Microsoft to:

Restore access for the original MSA that owns the Azure for Startups credit, or

Manually attach the approved Azure for Startups credit to a valid subscription in my tenant, or

Provide the correct recovery path when an Azure Sponsorship/MSA identity becomes orphaned after Entra tenant setup

At present, I have no way to proceed, even to request help, due to the identity/billing lockout.

Session ID: ba854a2f1b894f7b92f00d4a82e83ac6

Error: AADSTS160021 – Application requested a user session which does not exist

Trace ID: ede2ccd3-2236-410b-a942-114c4cd4bb01

Correlation ID: e5502eb5-4493-4df7-a1ef-c7ad0738be70

Timestamp: 2026-01-05 02:53:23Z

Client ID: e6694c91-1590-4e35-9bb7-b865c638b9c1

Scopes: 959678cf-d004-4c22-82a6-d2ce549a58b8/.default