Bad internet connection

I can't say that MTN has the worst internet in South Africa because I haven't made use of all the service providers in South Africa. However, I think it is a fair assumption that their internet is one of the worst, as I can't imagine any other internet connection being as bad as ours. We've had a data contract with MTN for years, but we are seriously considering switching as we are fed up with the poor connection all the time. I can't even make a decent call on WhatsApp without their being problems. Our bill has also suddenly almost doubled in the last few months. I see no point in paying this much for bad internet to be honest.