The normal water level for the high setting would be about 14" of water in the tub without clothes in it. The water usually reaches the third hole down from the top in the washer basket. If the washer underfills and begins agitating, it is likely that your water level pressure switch is bad.
If the washer fills to a lower water level and stops (does not start agitating), you could have a problem with the ETC (Electronic Temperature Control board) or the water valves. If this describes your problem, test the fill using just the cold water setting. Then test the washer fill using just the hot water setting. These two settings do not use the ETC board. If the washer fills normally on both of these settings, then your likely failure is in the ETC board or the wiring from the board to the water valves. If the washer fills properly using one temperature and not the other, then you likely have a water valve problem. If the washer underfills on both of these settings, then the pressure switch is likely to be the failed component.
I recommend conducting these fill tests to determine your likely failure. If you are uncertain which component needs to be replaced, resubmit your question with additional details or call a service technician to diagnose and repair the washer.