Poor signal service

I am staying in Sodwana Kwa Zulu Natal the service from Vodacom is so poor that there were many times in the last 3 year that I had to send my clients home with out payment and hope that they will come back the next day to pay cash as we could not use the card machine because of poor signal. Everybody in Sodwana have the same problem. They told me this week that they will cancel my contract free of charge because they can't do anything more than the router that they installed. I refuse as we were promised better service this year and had to stick up with the poor service all the time. The arrogance that we have to endure when lodging complain with the call centres. We depending on the internet for our bookings for our lodge and the diving. We loosing lots of bookings as a result of the poor service.