Hi Anis,
Thank you for bringing this issue to our attention.
So to answer your questions as best I can. Yes, Admob only allows one account. And you would need to fully delete one account to start another.
To start with you will need to
cancel your first account and then create a new one if you want to. But the biggest thing is that we will need to confirm your account which will usually require us to send you an email. From what it sounds like, you have lost control of your email too.
That link should also have some ways for you to try to reclaim your Admob account.
Regards,
William Pescherine
Mobile Ads SDK Team

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