There can be number of reasons for your problem.
Low fluid, level on the pump a broken belt, there is a belt that connects the engine's main drive pulley to the power steering, alternator, air conditioning, pulleys.
Or the power steering pump can go bad.
Check the fluid and the belts to make sure they are correct.Belt should have correct tension for it to work correctly.
All modern cars, belt tension is set with a spring loaded pulley to maintain the correct tension. Check the belt tensioned for correct tension
Power steering rack - the thing that couples the hydraulic pressure from the power-steering pump into the steering mechanism - may need repair by rebuilding or replacing with a used good one or new one.
Tire Pressure low. Front alignment incorrect. Front axle kingpins or ball joints tight. Steering gear improperly adjusted
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