I ran into an awkward situation.
Someone at the ATT fulfillment center forgot to input my apartment number, as a result UPS returned my shipment to ATT and I got a refund in about a week. I was first told to place another phone order use the offer link, which disappeared when I wanted to do so.
After several phone calls/secure messages, I was able to place an order on the phone with the help from a ATT CSR. And a Citi specialist asked me to send a copy the the receipt by mail or fax. The fax number is 1-866-799-5591.