TWO months of no internet but still paying

So I downgraded my line from 1g/s to 30Mb and this was at the end of March when that happened my internet stopped working and after hours of trying to get it sorted, I still am struggling with it. Now that I reversed payment for march I'm getting emails threatening me with legal action. I don't understand why I should be paying for something that doesn't and hasn't worked for two months. I'm tired of being sent from pillar to post by you people. Sort it or please cancel my contract cause what you are doing is ******* at its utmost proportion. i feel like a bushman being traded a mirror for an acre of land.