RETURN PROCESS NONEXISTENT

I purchased a pair of sneakers online on the 10th June and logged a return for these on the 17th of June. I am still waiting for them to collect the return in order to refund me. I have contacted them numerous times via calls and emails and the only answer I get, is it is being escalated. I cannot understand how when they have so many other competitors, how they can deliver such an appalling service. Do not purchase from this store!!!!