Refund pick up from imile to shein

I have submitted a return with shein through imile. Its been 20 days since I logged the return. They are delaying my refund from shein. I have sent numerous emails and no one answered me back. When I try and call the company it sais number does not exist or its engaged. I have tried the WhatsApp route with absolutely no luck or help from anyone. This is very unprofessional and unexeptable. All I want is just some form of assistance from anyone.