Invoices of items send

A lady from KZN send a parcel pin to me which was not my order. I opened the bag and after a week the ladies got her parcel from me but 3 thing was short in bag. The sender now says i took it.do pep stores invoice everything that you put in the bag or are the sender just put it in and send.is there any trace of the contents in the bag.will that pep where it was send from assist me