Azure subscription blocking tenant deletion is not visible in portal

I am trying to fully delete an old Microsoft business tenant and remove the payment method associated with it.

Microsoft 365 Support told me there is still an active Azure Plan tied to a subscription ID beginning with:

b69004a5-****-****-****-858ab8a325c8

They said this Azure Plan is preventing both removal of the payment method and deletion of the tenant.

However, that subscription is not visible anywhere in my Azure portal.

The only Azure subscription I can see begins with:

b4231b65-****-****-****-eefa4e5977c2

I already canceled that visible subscription.

I have also:

• Canceled the Microsoft 365 Business Standard trial
• Removed my custom domain from the tenant
• Canceled the Azure subscription that was visible to me
• Confirmed that Azure resource access for my Global Administrator account is already enabled

When I try to delete the tenant in Microsoft Entra ID, it still reports Azure-related prerequisites. When I try to open an Azure support request, the Azure Plan identified by Microsoft 365 Support is not available in the subscription selector, so I cannot create a case against that specific subscription.

My questions are:

1. Where could this hidden Azure Plan be coming from if it is not visible in my Azure portal?
2. How can I determine which billing account, billing profile, or Microsoft account it is associated with?
3. How can I cancel or disable it if I cannot access or select it?
4. Is there another way to reach Azure billing/subscription support when the support wizard keeps routing me to self-help documentation?

My goal is simply to remove the remaining Azure billing dependency so I can remove the payment method and delete the tenant.

Thank you