Paying double for a service and its not the customers fault

Last week my wife paid for a locker to PUDO a package. When she arrived at the locker, the locker displayed that there are no empty lockers. The next day after 14:00 she returned and the locker displayed again "no empty locker". She drove to courier guy kiosk Klerksdorp. She explained what the locker displayed. The lady then said she needs to use another locker and then said the other 2 lockers in Klerksdorp is out of order and she needs to drive to Alabama Twin tower mall. My wife asked when are the going to empty the locker. The lady at courier guy phoned the guy and he said "he is not going to do it again today". My wife then asked if she can hand the package in here and the lady replayed and said "yes but its going to cost you R105" Why double pay for a service where it is there fault in not suppling the service that was already paid for.