Watertight Continuous Gutters

My gutters were installed and I paid in full on 10/15/15. There is a stretch of gutter on the back of the house that is leaking between roof & gutter. I've been calling but no luck in getting them back out to resolve this issue. It's now 12/8/15 and I still cannot get them to return my calls or fix the problem. I do not recommend if you are looking for someone that will back up their work.