city of san jose trees and sidewalks dept. Duran Construction group Bill me for unfinished incomplete work, poor job, excessive charge, no authorization san jose California

BBB and DCA recommended to Duran to return $2500 to the city, and have another contractor finish the job. They will not finish the work they started and trying to bill me for it.  (treesAndSidewalks dept. of san jose city) did not complete work on driveway and sidewalk, now a water drainage issue.  Duran Construction Group showed up at our home on Wednesday 5-24-18, and proceeded to tear up the driveway and sidewalk.  Nothing was wrong with the driveway and sidewalk (probably got wrong address).  In the process of tearing up the sidewalk they broke the water main pipe and proceeded to fix the water pipe.  They left a one-inch gap between the new concrete and the old concrete sloped driveway, which is lower than new concrete. Causing water drainage issue (water under sidewalk will cause cracks and buckling).  They did not finish the job, there is still a one inch gap between the sidewalk and driveway which was not there before  (worse now).  We did not even authorize the work to be done (taking advantage of senior citizens).   Duran Construction Group damaged our driveway in six different places (concrete chunks missing). Duran was supposed to come out last week to repair damage, but never showed up.  Finish before city billing us.