Newgistics also "lost" my phone

I pre-ordered the iPhone 6 Plus in September on the first day possible. Even stayed up until 2:00AM to order it. The phone finally arrived on 10/10. I attempted to return the phone in store to get a larger capacity. I was told I had to mail the phone back due to it being a pre-order. The phone was never even opened. I placed it back in the original shipping box and placed the supplied retun label on the box and gave it to the USPS on 10/15. It showed up in their system AND Newgistic's system as "picked up". From there it is a mystery. I've called AT&T just about every day since the 15th and I get promise after promise of refunds and "escalated" tickets. I don't know how many hours my wife and I have spent on the phone getting the same empty promises from a different person each time.

At what point will they finally help?  Do we need to post this on Reddit? $115 may not sound like much to corporate AT&T, but to us it is a large amount of money.

As of last week, week of 12/8, the tracking number no longer shows up as valid on Newgistics website. Coincidence? 

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