A big brand like yours Mercedes Benz? for this nonsense?

We got sold a Bidvest warranty buy Mercedes when we purchased our Pre owned car in Centurion, a whole Mercedes Benz GLE and now when we experienced mechanical problem the closed dealership is Polokwane and they say they don't work with Bidvest, how come? so now the car has not been checked and nothing at all because we have to run around making claims ....imagine for a big brand like Mercedes is like we bought our car in the streets. honestly i am very disappointed. when i call back to centurion dealer why did you see us a product that you know is not accepted by some Mercedes dealership. no answer, called finance manager nothing, she tells me call Bidvest and explain the problem. we were under the impression that we have a Mercedes warranty and we can actually get the car fixed anywhere but that's not the case. mind you we stay in Thohoyandou, travelling to Polokwane with no assistance because that's the closest dealer in the province.