Я купила новый номер телефона. Пытаюсь привязать его к своему iCloud и iMessege, но система пишет, что он уже используется в другом аккаунте

Translated by google:

>>I have a new phone number. I am trying to link it to my iCloud and iMessage, but the system indicates that it is already being used with another account.

Hello. I have a new phone number. I am trying to link it to my iCloud and iMessage, but the system indicates that it is already being used with another account. Attempts to reset the password for the previous owner’s account are unsuccessful because the system does not accept the phone number as a valid Apple ID. I have a contract from my mobile carrier confirming that the number now belongs to me. Please help me forcibly unlink my number from the other person’s account.<<

Sorry, but this is a user to user community and we can not access your personal data and settings, only the official Apple Support can do that.

You should contact them directly by giving them a call:

К сожалению, это сообщество пользователей, и у нас нет доступа к вашим личным данным и настройкам — это могут сделать только специалисты официальной службы поддержки Apple.

Вам следует связаться с ними напрямую, позвонив по телефону:

...

copied from: Contact Apple Support - Apple Support

My attempt to reset the old owner's password fails because the system doesn't accept the phone number as an Apple ID. I have the carrier's contract stating that the number is now mine.

Since you talk about resetting the "old owner's password, to me it looks like the issue may be more fundamental and the phone may need proper preparation for you as an owner. Read this support article about what to do: What to do before you sell, give away, or trade in your iPhone or iPad - Apple Support

Some contributors to this forum will reply with a definitive statement saying you absolutely must use a number that has not been used before. What Apple says is in this support article: If you can’t create an Apple Account or see “your account cannot be created at this time” - Apple Support and is more nuanced, saying that if you see a message telling you to use a different number then you do need to use a different number.

“If you’re trying to create an Apple Account and see a message that says the email address or phone number is unavailable or can’t be used, then an Apple Account already exists that uses it. Try a different email address or phone number, or reset your password for that account ( If you forgot your password and can’t sign in to your Apple Account - Apple Support ).”

The easiest way to find out if you can use the same number is to try it. If it doesn't accept it then use a different number.

To contact Apple, go to this page: Contact Apple Support - Apple Support

(Although you post in Russian I do not automatically assume you are in Russia so the link I provide is more friendly on this international forum).