Private company issues parking ticket for no reason?

Private companies can issue you parking tickets only if you have broken the code, for California its 6.0.2.CPC which clearly says No Trespassing in private property, Most of the private properties, which has single road connecting to property are also considered as private property, Many times we miss warning signs which warns us to stay away. Go check again if you missed any signs and or make sure road is PUBLIC road not private property.