Unprofessional conduct

A cashier forgot a tag in one of my items, when I got to the door a the door Alarm went off or whatever is triggered when tags are left on. We first ask for the manager because the security was going through all items looking for what was triggering the door Alarm but we were told the manager went down. After that the security went to the till apparently and took of the Tag and apparently she gave the item back to me. My problem is I am missing that exact item that was apparently given back to me and just the conduct in the situation was simply very unprofessional and I lost an item in a situation that could of been avoided