Hello, @Omar Fahnbulleh !
Why am I getting an error message saying "At least one Azure plan must be enabled on the invoice section to create a subscription"
when I try to create an Azure subscription?
When you are trying to create the subscription, your default billing account is the M365 billing account. You can't create Azure subscription under it. So, in the Create subscription window, you need to manually select your Azure billing account. Afterwards, you should be able to select an Azure plan.
Reference:
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