Hello I have been receiving this notification since last ten days and I have received other notifications which confirmed that my device has been hacked and damaged and my privacy is in danger. I don’t have a money to pay for protection applications.

That is a Rogue Calendar account. 

If you are using iOS 13 then Go to Settings ➔ Passwords & Accounts and under Accounts see if an unknown calendar account is listed. If it is then tap on it and then Delete account.

If you are using iOS 14 the Go to Settings ➔ Calendar ➔ Accounts and under Accounts see if an unknown calendar account is listed. If it is then tap on it and then Delete account.

Note that it is not a virus or a hack. It is something that got added to your calendar because you may have accepted an offer from a pop-up on a website unknowingly. Please be careful out there.

Axel F

You are welcome.

Axel F.