Equipment

I was with ATT U-verse years back and i did everything good to cancel with ATT. I was able to return 1 equipment because FEDEX would not take the rest because the rep that helped me only sent 1 barcode for the main equipment. I have tried to get the other ones sent back but it has affected my credit. It is not my fault the rep only sent 1 barcode and now I have to pay for it, is there a way you can remove from my credit if I send the equipment back since I do still have it???