DSV - Parcel not delivered for almost a month

I was supposed to receive a parcel wit textbooks from UNISA library which were dispatched beginning of April. I've called numerous times but have been goven a run around by DSV consultant that says they are given their team time to locate. I am being charged daily for not returning the books on the due date to UNISA. The same books that were not delivered and still not located by DSV. I am frustrated as I don't seem to get prompt feedback and have to call several times using my airtime only to be sent from pillar to post