Q: Reduce Engine power and nothing happens when pushing the gas pedal

My truck starts but When started a Service 4x4 sign comes on and the Reduce engine power and when you go to step on the gas nothing happens. We took it in and the code ran was the Throttle position Sensor and we changed it out but it continues to have the Reduce engine power thing come on and when i push on the gas pedal its like its not connected because the engine doesnt rev or anything

My car has 172000 miles.
My car has an automatic transmission.