Had that problem last week. My 2006 AMT would change from auto to manual while I was driving, and then it would get stuck on one gear and won't let me change till I stop, turn off the engine, and start up again. I took it to the authorized Proton Service Center nearby and they replaced the accumulator for RM 1.2k.

After I got it back, I drove for less then 4 days, and the same thing started to happen. took it back to the workshop and they said it was the motor so... it's been at the workshop since Wednesday.

I think that after I get it back I will go car shopping.