Hey Priyadharshini!
Are you using the same email? As far as I know this should be use when for example you start to work on a new company then you should have your old email: email1@oldcompany and your new email2@newcompany. So they should be different.
If you are inserting a different email address I would tell you to open a ticket on support they can check whats wrong and take some actions to fix the problem.
I had a problem with my account in the past and they solved it.
https://support.mendix.com/hc/en-us
Kind regards,
Emilio