Thank you for posting this in Microsoft Q&A.
I understand you are having trouble starting the Microsoft Entra ID P2 Trial even after entering and confirming their credit card details.
Also did you get a chance to refer these QnA posts where similar issue has been discussed - https://learn.microsoft.com/en-us/answers/questions/1464265/i-cant-activate-the-trial-of-microsoft-entra-id-p2
If the above posts don't help, help me with more details like have you able to click save option or did you face any errors while click the save option.so that I can better understand the issue and assist you.
Thanks,
Navya.
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