Somebody else got my order

I order tapes from them as a replacement for an order that they cancelled because there was no stock of the item I wanted and then it was collected from the branch by goodness knows who and now they can't even tell me or are willing to replace my order, they hide behind the fact they sent an email, yet all my orders when I collect show I collected it expect this one has apparently got a staff members name behind it, so what now I must just go without my order? I queried and they just closed the query with the excuse somebody else had access to my emails.