Hi,
I see the below when I add email details on Reassign in Power Automate
Thanks,
Hi @krishnna
Is the user you are planning to reassign to a guest user?
Please note that if you assign a guest user to an approval, that user will not be able to bie or act on the approval by default. The guest user must be assigned a valid Power Automate license (per user license or Microsoft 365-based user license) to view or respond to the approval.
More information please check the below link:
Known issues and limitations - Power Automate | Microsoft Learn
Also, since the approval's data is stored in Dataverse table, you could check and grant the Assign permissions to the user by going to the Approval table > Share > Manage access > Grant Assign permissions to the user.
More details please kindly check:
Check your user access and permissions - Power Apps | Microsoft Learn
Power Automate: Reassigned approval tasks' permissions in Pow... (hubsite365.com)
Hope it helps!
Best regards,
Sylvia