Riding mower will not change direction unless I hit the brake

Hello,

I have a crafstman riding mower with a hydrostatic transmission. It was working fine without any issues. This issue started suddenly. I can’t seem to change direction by using the shifter. If I am going forward, and come to neutral it stops. When I pull the shifter into reverse it starts moving forward instead of backward. If I hit the brake, then it switches direction and starts moving backward. The same happens when I try to switch directions from backward to go forward.

Even though I am able to move the shifter all the way from forward full speed to backward full speed, it feels very forced (as if the shifter is stuck on the inside and the lever is moving under force).

Also, even with the freewheel lever pulled all the way out, I cannot push the mower freely. My mower has always been like this. Should I be able to easily push the mower when the freewheel lever is pulled all the way out?

I already did the transmission purge. Any ideas on what might be wrong? How can I fix the two issues?

Thanks,