Packaging opened, missing item on order.

Ordered from SHEIN and Buffalo happened to be the courier. The parcel got delivered at work, when I went to go check the parcel, the packaging was opened at the corner and to my surprise, there was an item missing from my order. Why was the packaging opened without my consent? Where is the item that is missing? I’m still waiting for my item or a refund because this is unacceptable to say the least.