Unhappy with Customer service.

I'm not happy with service that I get from Mr Price promenade mall branch. I went to exchange some items and supervisors told me that their system is offline and the is nothing they can do.When I contacted the customer service department they gave me the number that must call so that I can know which store is not offline so that I can go to that store even if it's in Johannesburg probably. Now I'm stuck with 3 items that are worth almost 1000 that I won't be able to use. Please help what the next step me.