Hello Floares Mihai-Ionut, the subscription is NOT restricted to US-only. Unfortunately, Microsoft doesn't publish the list of colleges that it considers under this program and so, there's no way to verify any specific college. The only thing that I think is missing based on what you have entered above is that you haven't verified your college email address which is a prerequisite. Alternatively, it could be entirely possible that the supplies has run out since they mentioned explicitly in the page that there's a limited supply of activations and the offer is available only while supplies last. See https://azure.microsoft.com/en-us/pricing/offers/ms-azr-0170p/
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