error_USER_NOT_MUTUAL_CONTACT

Sorry, iIf a person is no longer part of ahas left the group in the past, you need to be in their Telegram contacts to add each other to your respective contact lists to be able to add them back.

Note thatThey can still join via the group's invite link as long as they could still join viaare not on the group's invite link as long as they are not in the removed uRemoved Users list.
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