Ordered wrong phone on Next Upgrade. Refused shipment, got credit..... now what?????

While upgrading my husbands iPhone 4 with AT&T Next, I ordered the wrong device. He asked for the iPhone 6 plus, but I clicked on the iPhone 6 instead. We called AT&T customer service and were told to just refuse the shipment since they were unable to edit the order. Next day, I refused the shipment from FedEx. 9 days later, my husband receives an email stating the device was received and a credit (for sales tax paid at check out) was issued. Okay, great!!!.....But, when I log on to select the correct device it says the line has already been upgraded and a new device cannot be selected. Grrrrrrr! On top of that, we are now in a AT&T Next agreement paying for a phone we don't have. An agreement that did not give us the $25 a month credit per upgraded line, like it stated in the advertisement email that started it all!!!

Now what do I do? I can't select a device until I activate one?!? This makes no sence to me.

Can someone please help?

Thank you in advance.