Terex TA400 Weird Shifting Issues

Hi! This is a 2010 Terex TA400 with SN: A9821095. The problem is a bit confusing, would anyone have an idea what could be causing this:

Let's say the vehicle is parked. The driver can start it, and shift from park to 1st. The shifter moves, and the driver can move forward. However, the truck will not shift into a higher gear. If the driver stops and shifts into reverse, the truck will still move forward in 1st.

After shutting off and restarting the truck, if you move the shifter...

Terex TA400 Weird Shifting Issues

Terex TA400 Weird Shifting Issues