Good afternoon, I’m from Ukraine, I bought a phone from the USA, and it was locked by one operator, how to unlock it, what would it be Never loock. I do not have the operator number that was when I bought it iphone. IMEL 354844093152661.

Good afternoon, I’m from Ukraine, I bought a phone from the USA, and it was locked by one operator, how to unlock it, what would it be Never Loock. I do not have the operator number that was when I bought it iphone x. 
I do not have the number of the mobile operator of another country, under which the telephone is tied. help me how to solve this proble

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