Your son, a minor, opened an eBay account.
He sold an iPhone 12 for $1200.
How did he get paid?
Neither eBay nor Paypal allow minors to sell on eBay. Partly this is because minors cannot legally enter contracts. Partly it is to prevent them from being defrauded, since most children are naive and easily fooled.
We'll skip the lecture about your parental duty to supervise your son. Somehow he got an expensive phone and sold it on eBay for slightly less than the current price.
What was the scam?
Did the buyer claim he did not receive it?
Did the buyer say it was not as described?
Did the buyer return something other than what was sent?
When was it sold?
When was it paid?
Did the buyer persuade the child to mail the phone before he was paid?
Did the buyer ask that the shipping address be changed?
Or was your son the buyer?
Did he receive anything?
Did he receive a picture or an empty box?
What was the date of the purchase and the date of the delivery?
Since English is not your first language, give details in your own language. There are enough sellers here who can read it and give you advice how to perhaps get the money back if not the phone.
