Was parked at a friend's apartment while GDE crew ...

Was parked at a friend's apartment while GDE crew was doing renovations, can out to my car damaged after one of the painting guy put a cover on my car without permission. I haven't received a call from the company in exactly 6 weeks. It's really unprofessional considering I've call numerous times! Luckily I'm a precistent person so I'll keep calling until I get an answer!