Cracked iphone- horrible AT&T Retail Store service

I had a little crack on the corner of my iphone 5s.  Continued to use it for over a year with no problems, no additional damage.  Then the screen cracked and was completely unusable.  I went in to a local, authorized AT&T retail store where I was told I qualified for insurance, but  would have to wait 5 days for a new one to arrive in the mail or they could fix the screen in 2 hrs.  Given the choices- I picked the later.  They charged me $130.  It took 3 hrs, instead of 2.  The metal frame was bent and it cracked again (normal use, no accidents, dropping, etc) in the exact same spot!! Who can I contact to complain about this retailer? 

AT&T Authorized Retailer

484 Avenue Of The Americas

New York NY 10011