Code p0717

Hey I’m just trynna find more information on this code I been experiencing slipping above 4th gear feels like I’m stepping on it when it’s in neutral even tho the car is in drive car also doesn’t go highway speeds without slipping. I’m thinking of replacing my valvebody but I haven’t got code p0720 instead I got code p0717 and can’t find much information on it ik it’s a sensor but would I have to replace my valve body in order to replace it.