Azure AAD subscription cancelled automatically

I’ve received an email stating:

“Back up your data while there’s still time

You’re receiving this email because you cancelled your Azure subscription on 04 June 2024. If you have data stored in this subscription, it will be deleted on 02 September 2024. Please log in and save any important data before then.”

The specific subscription it references is “Access to Azure Active Directory” and is used by my M365 dev tenant (as I understand it). I haven’t cancelled anything and don’t appear to be able to raise a support ticket online. What is going on?

Thanks

Mike