Mango Clothing stop ******** me, pay back what’s mine

My order number is DOHBLT, i had purchased a dress a month ago and it did not fit. Requested a return and refund, and it was collected by the courier company. Till this day i have not received any feedback. I emailed them and was told that 2 weeks later they had not received the items in their warehouse, how long can it take. I want my money back, their clothes are super expensive and there’s no way i am letting this one go.