Shein Reimbursement Delay and Poor Communication

I placed an order for over 400 lira from Shein. I requested a refund. The site says the money has been sent, but when I called the bank, they said Shein hadn't even submitted a request. I can't reach them. I don't understand when my money will be deposited, or if it's reliable. I can't find a customer service number either. I couldn't find any information about refunds.