Authentication problem

Hello, my name is Marcu, so I bought an iPhone X 64gb on a second-hand about 6 months ago, connected it with my Apple ID, and I used it normally, but I had a problem with updating it, it was working on 13.7 IOS, till yesterday, when I found out how to update it to latest version of IOS, and I updated it through iTunes, after restart, phone required form me an Apple ID to activate it, but when I put my Apple ID it didn't work, it required me another Apple ID, so I got blocked here and can't pass this authentication problem and I can't use my phone.

Have to say also that phone saved my changes it name is "iPhone X Marcu" and also my dates are in because the storage is full for 54gb from those 64gb.

Thank you, and I hope you will help me somehow, or change the activating Apple ID to mine.

SN: DN***CLH

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