Monotronics Alarm Monitoring company This company continued to take payments from my checking acct. for 2-3 months after i wanted the service discontinued Nationwide

Monotonic alarm company would not stop taking money from my checking acct for ,2 -3 months after I had called to discontinue the service .  In Oct. Of 2013 we sold my mother's house where the alarm system was.  It took several calls c to this company to finally get the payments stopped.  I thought everything had been taken care of.  Now 17 months later I get a call from a collection firm for another months billing that they say I never paid.  They actually billed me longer than they should have and I am sure this is for a month I didn't want their services.  I never got a refund either.  Now I am called threatening my credit!!  I see other complaints regarding their practices.  Everyone should beware of this monitoring service and their billing practices.  The hardest company to sever from I have ever dealt with!