I bought my iPhone in a store but its model number is 5Q9X3ZD/A

I bought the phone in a store, but its model number is 5Q9X3ZD/A + After checking on the official website, it is written that the warranty expired in April 1978. The seller claims that the phone is new and has not been refurbished or previously used. Help me solve the problem. The phone was not activated, I activated it myself. But the warranty is strange + strange model number that I have not seen before

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