I haven't received my refund from buffalo

I place an order at shein on the 8 of February 2024 which was delivered to buffalo ,when i checked my shein status on the 21 Feb it says my package was delivered wilhich i did not received ,i had to call buffalo and ask them where did they drop it ,they told me that their truck was hijacked with my order ,firstly they didn't call me and let me know ,i had to call them ,secondly they send a refund form which i filled and send it back to the them with proof of payment ,i haven't received my refund even today ,I'm not happy at all with buffalo ,i hope shein will change their courier in future before lossing customers