Hi @Nolan Lemuel Augustine ,
I used the Free Trial option of Azure Entra ID/Azure Active Directory a couple of times .
Every time I got some notification emails with information my Free Trial period will end soon. Also there is an information in the mails I have actively move/switch to the "pay version".
Never there was a "automatically switch" to the billed/pay version of the Free Trial product after trial period ends. The Azure AD/Entra ID tenant automatically reverts back to free version.
(If the reply was helpful please don't forget to upvote and/or accept as answer, thank you)
Regards
Andreas Baumgarten