Holden Commodore 2014: Trouble change gears

I have owned a 2014 VF Commodore SSV, 6.0-litre 6-speed for two years and have a year to go with the warranty. The complaints I have vary, from a leaking radiator, which took two years to fix, the air-conditioning doesn't blow cold enough air, and my gearbox hasn't been able to change gears without going slowly or doing a double clutch. After it sat for six weeks while I was overseas, I couldn't get any gears to work. It took 30 minutes with my car running before I could get my gears to work. I've been complaining about this and other things for the two years that I've had the car and it falls on deaf ears. Can you please help me?