How do I close/cancel my AdMob account?

Question

Google AdMob

You need to cancel your AdMob account in order to pay the earned balance. Tried to delete an Adsence that I didn't use, but the error occurs when canceling:

Unfortunately, your account cannot be canceled at this time. Possible reasons: Your payment status has changed or you have used the link in our email after more than 24 hours.

But I didn't make any changes to the account.
There is nothing in the AdMob account settings about closing.