Returned streaming device

I bought the streaming device when I signed up and paid in full $127.20.  The first one turned out to be used, and failed after a few days. They sent me a new one that failed also.  They emailed me a return slip.  The tracking number says they received it 16 days ago.  My account says I still have it and, of course no credit was given and I got no notification that they received it.  I've done a charge back since what else can I do.  On line chat is with a robot and not a human and fails miserably at giving advice.  So is it reasonable that it would take this long to fix my account?  Also, before you say it, the device has a 2 year warranty, and between the two devices I had, I did not have it over 14 days.  Also, how fair is it to keep the one I sent back and give me nothing.