I'm really sorry to hear that your phone line has not worked for some time, and I'd really like to get things sorted for you.
I'd also like to thank you for letting me know that you've already tried a new phone on the line, as this helps eliminate the phone from being at fault. The next step to get things working for you would be to arrange for someone to call out and check out all the connections.
So I'll send you a private message in order to get things moving on this. Please look to the top right of this page where you'll see a little purple envelope icon, Click on this an you'll see my message.