Installer never shows up!!

I have found the Direct TV installation process the most incompetent system i've ever come across.  i requested an upgrade to my satellite dish from SD to HD.  My SD box was inactivated.  since then, i have had over 10 installation requests over the past 3 months, but the technician NEVER calls and has never shown up.  recently, they just cancel the appointment and move it to the next day and keep moving it.  They have done this now over the past three days!!  i cannot believe it.  I've spoken to numerous technical supervisors and no one has been able to help.  i feel like im being held hostage.  no TV service now (my SC box has been inactivated).   I am at my wits end.  Does anyone have a suggestion?  Has this happened to anyone?  im on the Suffolk County, NY location.  thank you