How do I get compensated for improper ATT equipment installation that caused 3 computer tech visits?

ATT offered my business combined phone and U-verse service to save me money.  I said sure.  Their tech comes to install necessary modem, but ignores the structure of my phone service (main line, rollover line to the main, third line for alarm and CC machine backup), installing wrong modem that disables my network and can't support the phone service that THEY ALREADY PROVIDE.  Rollover line non-existent, third line dead.  Second ATT tech tries to fix lines, doesn't, again disables my network.  Third ATT tech sees it is the wrong modem, does the job right, but my computer tech has to show to be sure he doesn't mess up network.  $240 of house call charges.

Sedgwick Claim Management's Logan Glenn says I gave away all liability claim on ATT by agreeing to terms of service at installation.  (I wasn't there at the time, signed NOTHING)  Anyway, this includes incompetence???

ATT techs cost me $240 by installing the wrong equipment, then say it is my fault they gave me the wrong stuff.  Seriously?  Will a human being at ATT step up here?  If not, I am gone as a customer