Order of Stradivarius Lost in Transit

I reached out to Stradivarius about my missing package that was shipped by Hepsijet, and asked them to send it again. Here is my order number: 50218240779. I placed the order on April 9th, and it's still nowhere to be found. Despite their promise to follow up, they have not reached out to me. I kindly request for the shipment to be resent and for them to respond to me in a timely manner. Otherwise, I'll be left with no option but to lodge a formal complaint.