From the FAQ
Once a nonprofit organization is validated as eligible, Microsoft requires that grantees regularly complete an attestation to our donor rules to maintain eligibility. Microsoft will send a reminder when an attestation is due, but it is ultimately your organization’s responsibility to complete the required attestation. Failure to complete the required attestation may remove eligibility for Microsoft’s nonprofit programs unless/until you complete the required attestation. Additionally, you may be requested to review your current contact details and provide any required updates.
you could also open a request via the portal for follow-up questions.
https://nonprofit.microsoft.com/en-us/contactus
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