iPhone X locked to Apple ID that’s unknown. Activation Lock removed multiple times. Any other options?

I want to give to my daughter an iphone X that I don't use anymore. It was mine, only mine, I never gave it to other people, I'm the only person that used it in the past.

So I deleted all the data, removed it from my devices and installed the new IOS, but after installing IOS it get locked by an hidden @icloud email that I never had. My unique apple ID ( I have an apple ID since my old iphone 5 or also from the very old ipod, more than 10 years ago) is with my personal gmail email. I never had an @icloud email.

I called the apple support, explained everything, sent them the serial number and the proof of purchase. After 1 day they sent me an email saying that they had unlocked the phone and that I now had to install IOS again.

I did everything as descripted on the apple webpage, but after that the iphone was again locked! Same message like before.

Done this process (calling the apple support) other 5 times, same story, they unlocked it and after I install the new IOS the iphoneX get locked again.

6 times in total, 3 month of time lost and I'm here again with my iphone locked. It's pretty new and in excellent conditions, and I don't want to throw it away.

I also went to an Apple Store, and they told me that ONLY by phone, from apple support, I can solve this problem. THe apple store can't do anything.

Is there any kind person who could tell me what I can do now Is there any kind person who could tell me what I can do now (other than throw it in the dustbin)?

Thank you very very much

Pietro

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