Why must I beg and wait 2 weeks for a missing item?

Made on online order on 11 October 2023. I was informed via email that one of the items I ordered was out of stock. I requested that the rest of the order be delivered without the missing item. I was told that I will be refunded for the out-of-stock item when the rest of my order is delivered. The order was delivered last Friday. I received box 1/2 of the item that was supposedly out of stock. It was supposed to be 2 boxes, so box 2/2 was missing. The driver said that was the only item they had to have delivered for me. I called the call centre. The lady told me she'll sort it out and then come back to me. That was this past Saturday. I heard nothing again from her. I called on Monday, I was told that the delivery company was instructed to pick up the missing item at store near me and deliver to my address. I call again today for an update, the lady over the phone dares ask me what item is missing. That should be on the system surely?! And that the delivery company will only deliver next week?! So I must wait 2 weeks because of a staff member that thought it fine to pack half an item?

Please come and take your half a product and refund my money. Or are you trying to delay so that I have to be stuck with half an item?!