Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Hi Ben
Thank you for reaching out to the Q&A Forum.
Firstly, I hope you understand that this is a public peer-to-peer community forum so while members can share advice and experiences only. For your privacy and security, we (moderators and other users) do not have access to backend billing data or credit card details. Specific issues regarding Power BI subscriptions and billing are currently not supported in this forum. Because this requires accessing sensitive personal and financial data to verify ownership, we cannot resolve this directly here..
Since you cannot log in to the old account to generate a ticket, and the phone system is blocking you, you can try to create a temporary Free Trial Tenant: Visit the Microsoft 365 Business Plans and Pricing | Microsoft 365 and click Try for free to set up a trial account.
Once the new business account is created, this will give you access to the Admin support portal where you can request a callback: Support requests | Power Platform admin center
For detailed information, you can see: Get Support in Power Platform - Power Platform | Microsoft Learn
This workaround allows you to bypass the automated phone system asking for the old account number and I sincerely hope this helps you get in touch with the billing team quickly.
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