Parcel was delivered at the dobsonville branch but it cannot be found

On the 6th of Dec '17 I received an sms from postnet that my parcel was ready for collection, sent someone to fetch it on my behalf and the parcel was not there. They called me and I was asked to give them time to look for it, which I did. The following day the manager called and asked the same thing from me and I understood that it might be misplaced in the shop but I got impatient a week later when no one got back to me so I decided to contact head office and I received an email where I was cc, they sent Sam and his team an email informing them to locate the parcel because it was signed in and at the branch they claim they don't know who signed it in but on the email from head office it clearly states the name of the person who received it. I just want my parcel or my money back I have been patient but now I am frustrated by how I am being treated. Will never use postnet ever again