Thank you for reaching out to the community forum!
For your query I have understand you're facing an issue with activating your Microsoft Entra ID P2 free trial version. during the process you are getting error **43881. ** We have researched on this error code and noticed few cases internally regarding this error, this can be resolved by contacting our support team, you can reach out to our support team - https://support.microsoft.com/en-gb/topic/global-customer-service-phone-numbers-c0389ade-5640-e588-8b0e-28de8afeb3f2 Get a case created with our subscription team they will validate your details and resolve this issue, further you will be able to activate the P2 premium free trial.
Hope this answer helps. Do let us know if you any further queries.
Thanks,
Akhilesh.
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