Gỡ id apple của người khác trên iphone của tôi

I had someone else log in with their apple id on my iphone

With their ID on the phone, the phone now identifies as belonging to them. Get that person to do the things in this article --> What to do before you sell, give away, or trade in your iPhone or iPad - Apple Support

If they will not, Apple can completely reset a device if a person can provide sufficient evidence of valid ownership. Check the requirements and steps at: Activation Lock support request - https://al-support.apple.com/#/additional-support Apple says, "Proof of ownership documentation is required," but does not detail what currently constitutes proof other than it “must include the product serial number, IMEI or MEID.” Apple may typically require the original receipt* issued by Apple or an Apple Authorized Reseller. If Apple resets the device this will give you access to the device but won't restore access to the account used to lock it. There is nothing that can be done to expedite an Activation Lock request.

*Apple recommends you "Keep your receipt after you buy an Apple device" --> Keep your receipt after you buy an Apple device - Apple Support