Replacement for non delivered merchandise

Back in november I purchased the FF14-Best music from the NA SE online store. It was finally shipped in early december but something happened and it never reached me. I've inquired with the Post office already and reached out to the store customer service about having the disc replaced or refunded but they have not responded to the multiple tickets and follow up emails I made.

Its been a month now and its getting ridiculous; at this point I'm ready to say screw it and call my bank for a charge back. Does anyone know any other way to get a hold of SE to at least get someone to respond to their customer service tickets?