Strange automatic glitch

Alright, so basically what happened is that I was just playing with the ambulance, driving around. Then, I respawn it and start to drive again. This is when I got the problem. The transmission was not changing gear, and I was only going 30mph. So I just reloaded the vehicle, and it still happened!
Please tell me if there is a way to fix it, as this happens often, especially when I try use a sports automatic.

 

cant duplicate

 

press q a couple of times until in the top left corner displays a message with automatic

 

I can duplicate it in a way.. every once and a while, i put it in D or R (using the h shifter on g27) and it wont shift out of N untill i put it in 2 or 1 then it goes but only those for about 2 minutes

 

did you try shifting down once or twice so that the gearbox went into second or drive. Sometimes people forget they are driving auto and try to shift up using the button but your in first gear.