The transmission is having problems. It struggles in low gears and won't reverse when car is facing downhill.The system lights are also on.
The transmission needs to be checked for a leak and the cause of the low fluid. This is why it will not work on a hill. The transmission needs more fluid for reverse and low gears and if it is low on fluid will suck air and cause your issues. You say the system lights are on but do not specify what light. The transmission being low on fluid or a sensor issue will turn on check engine lights and will need to be scanned for codes and diagnosed by a qualified mechanic like one from Your Mechanic.
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