Mismatched sneakers recieved and poor customer service

I purchased a steve madden taupe sneakers online and received two mismatched sneakers 1 black and 1 taupe. I contacted Steve madden who arrange a collection with Rams couriers and promised to deliver the correct colour and size. Rams couriers have asked me to change to collection address to my work address and I agreed. The next day they did not collect. I then called Rams couriers who said that I must now call Steve madden to log a new return collection reference. I am constantly emailing the call center and they said they have changed the address and will resolve it however they are not responding to my emails or calls. Rams cannot collect without a new number. Chanel and Leah from Steve madden have been ignoring me since yesterday. Worst customer service ever recieved. They aren't even answering calls!