Worst network coverage ever!

Ive had it wirh MTN, I have been complaining for iver a year regarding NO SIGNAL on our farm. I provided 5 alternatives numbers that also does not have signal. The answer I am getting, there is no fault, your query has been escalated, for a year??? MTN is very fast to suspend a line when a payment is one day late, but why am I paying for a service that you CLEARLY CANNOT PROVIDE!! I dont know what avenues to follow anymore, I have exhausted all options and I am not getting anywhere!