Shein Claims My Order Was Delivered but I Haven't Received Anything

I ordered items from Shein and later received an email from Buffalo stating that my package was delivered, but I haven’t received anything. I called Buffalo to check, and they informed me that their system shows the parcel as delivered, yet I haven’t received it. They advised me to wait 72 hours for feedback. The most frustrating part is that I didn’t even get a call to notify me they were on their way, as they usually do. Please help me resolve this.