Refund not received

I ordered a few items online from Shein, but I decided to cancel it due to the coronavirus since it was a package coming from China. For 3 months I have been battling to get my refund back. I liaised with my bank and Shein. Shein sent me proof of payment but the bank says it doesn’t have any record of it. I am stuck in a place where I feel like I am being ****** of my own money. It is just under R1000 I am still waiting for and I don’t know what else to do.