Heavy vehicle parking infringement
I received a parking infringement for parking a heavy vehicle for over 1 hour in a built up residential area. My question is what am I supposed to do for parking? It's a tow truck that I need close to me at all times as I clear accidents and stolen vehicles in Melbourne for the police(I don't work for the police we just have the contracts for it). It is somewhat considered an emergency vehicle but not when it comes to parking.
For context I had parked next to vacant lots to not annoy my neighbours as the spots next to my house are permanently parked in by neighbours. Is there a way I can get out of this fine? Its my first one ever and tbh didn't know it was a thing. Is there a way to be exempt or a permit or something I can do to not have to get random parking fines at 9pm on a Saturday?
Thankyou
Edit: city of whittlesea