vivint security system  will not cancel my contract an i only have 14 months letf. provo , Utah

I was pressured into buying a security system for my house. But i did not need it but had it installed an i had the same phone system, but changed it an went to cable an that did not do anything to the srevice. Now i went back to the phone service i had before with fiber-optic cable an the system doesn t work right an they tell me to get different cable or buy a new system. They won t even work with me to resolve this. an i still have 14 months left on the contract an if i stop paying they will turn me into the collection agency which i think is very wrong that they won t work with me can anybody help me.