We made some changes to the Microsoft Developer program and revised who all are eligible for the same. So, please make sure that you fall in the set of eligible individuals by looking here -- https://learn.microsoft.com/en-us/office/developer-program/microsoft-365-developer-program-faq#who-qualifies-for-a-microsoft-365-e5-developer-subscription-. It's likely that you don't fall into this list. In case you're in the allowed list of subscribers for this program and still face the same issue, the easiest way out for you here is to create a new personal Microsoft account (like Outlook, Live etc.) and sign up for the Microsoft 365 Developer Program using the new account. It'll unlock the program along with the Power Apps Community Plan.
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