Transmission not shifting out of first gear

Good morning,

Is the check engine light on?

https://www.2carpros.com/articles/automatic-transmission-problems

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

The throttle position sensor controls the shift points for the transmission. If it is bad, it should set a code.

I would start by changing the fluid and filter as nine months is a long time to sit.

https://www.2carpros.com/articles/how-to-service-an-automatic-transmission

Roy

1. Remove the air cleaner outlet resonator.
2. Disconnect the throttle position (TP) sensor harness connector (2).
3. Remove the throttle TP sensor screw.
4. Remove the TP sensor and seal.