Good day, when running a quick 5 lap race, I find that the lap counter only runs to lap 3 and then stop counting. This means that the race does not run for the full 5 laps. I normally start at the back of the grid, but any position I held at lap 3 then reset to the last position - it even indicates the last position on the car ( GT 3 ) although I was one of the front runners at lap 3.
Could be possible that you have setup the race to laps and time? In this case, if the time finish before the lap, the race could end in the lap three.