Ford South Africa

I bought a new Ford Ecosport 4 years ago. Since I received my car it gave me a problem, ie the sensor on the wheel indicate that I have a flat tyre. Which is not the case. I took it to Ford Fezina numerous time and they only reset the error. I already report this issue to Ford Customer Service but with no luck to sort out this problem. I request that the sensors being replaced but their answer is that it is too expensive. I cannot drive with my car as I would like to because I am scared that the error appear when I am in the middle of nowhere and must stop to make sure that the tyres do not have a problem. This is not save for me even to drive at night. I would like to bring this to somebody's attention to investigate my problem. I cannot afford to replace the sensors as the vehicle was brand new when I bought it.