Phones Stolen in Transit - ATT making us pay

I ordered 5 brand new iPhone 15s. ATT shipped it to us but we only received 3 phones. I went into the ATT store and the sales rep confirmed that it was stolen in transit as the shipping box was too small to fit all 5 phones. He then gave me 2 new iPhone 15s on the spot to replace the stolen phones saying it wasn’t an issue since it wasn’t our fault and we wouldn’t have to pay anything.

Days later, I get a bill of $2k for the stolen phones. I spent hours on the phone with multiple ATT agents and each one tells me I have to pay the bill. I even went back to the same sales rep who gave me the replacement phones and he said it is now out of his hands and the only thing he could do was put in a ticket. Well, that ticket has been denied and they still expect us to pay for the stolen phones. I’m at a loss for words now and have no idea what to do.