Hello Parag Dessai,
Welcome to Microsoft Q&A!
I understand that you are having trouble reactivating your Microsoft 365 Developer Program subscription. If you have not tried it yet, please try to go to the Microsoft 365 Admin Center > Navigate to the Billing section > Locate your expired subscription and click on Reactivate.
If reactivation isn't possible, you might need to set up a new subscription. Unfortunately, if the subscription and data were deleted due to inactivity, it may not be recoverable
If you're still facing issues even with a new subscription, I would recommend you react out to Microsoft support: Contact Us
I hope the information provided is useful!
Regards,
Gao
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