Bad service from big boy s******s

I'm disgusted in the service I'm currently recieving at big boy s******s in pinetown.my bike is this from last year 2018 November till now n I always got to call them they don't ever call me or return my calls like they promise and failing to fix my bike since last year without any valid reasoning.all the reasons they gave me sounded like excuses and I've had enough please advise me on a way forward as they have already stripped it down to pieces