Shein has red flags

I have purchased from Shein 3 times before and had received my order in record time. I made a purchase of R3179 in Dec 2021 and my order required a tariff fee of R660. I then canceled the order and it was sent back and I received a message from Shein when they had received the package. They claim to have sent me my refund which I have not received till this day. They have also failed to provide me with a proof of payment to my account. My bank has had to intervene.