It is likely that an insufficient permission level is preventing you from changing the email address format for an Active Directory user. To troubleshoot the issue, you should:
- Verify that you have permissions to update the issuer’s email address.
- Check if the issuer is valid and enabled in the Active Directory.
- Search the applicable logs for error messages.
- Test to see if the email address is being accepted when attempted in a different format.
- Confirm that the domain host is correctly configured with the same settings as the issuer’s email address.
