@ayodahunsi , thank you for the question.
Please review the article below which contains detailed steps to transfer the billing account of an Azure subscription.
Transfer billing ownership of an MOSP Azure subscription to another account
Before you transfer billing ownership for a subscription, read Azure subscription and reservation transfer hub to ensure that your transfer type is supported.
You could also reach out to Azure Support for detailed assistance with your subscription management. Note that "Billing and subscription management support" is available for free for all subscription types.
Hope this helps.
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