Cannot assign global admin rights to myself — sole user of Business Basic subscription -sigh

I’m the sole user and administrator of a Microsoft 365 Business Basic subscription, purchased directly from Microsoft (not via a reseller). I’m unable to assign global admin rights to myself, and I get the error: “You don't have the required permissions to access this org. Talk to your IT admin for more info or switch to another account.”

I have no other users in the tenant, no third-party admin, and no CSP involvement. Teams and Microsoft 365 won’t allow me to configure admin roles, access the Admin Center properly, or raise a service request. Even though my subscription is active and paid monthly, I’m stuck in a permissions loop without access to support.

Support channels have been inaccessible:

• The UK support number (0800 032 6417) disconnects immediately.
• Admin Center does not show “New service request” or live chat options.
• Services Hub gives a message saying I need to contact my Microsoft account representative — I don’t have one.

I urgently need assistance in resetting admin access or reconfiguring the tenant so I can use Teams with calendar integration and recording features. Please help me resolve this.

Thank you.