I have a 2004 chrysler 300M. A few days ago it started shift down hard from 2nd into 1st gear when I am slowing from a higher highway speed. After is shifts down hard it won't come back up out of 1st gear. It doesn't seem to help for me to put it into neutral or reverse and then back into drive, however if I completely stop, put it in park and turn off the car, then restart, it is like it has reset and it works fine again until the next time. What could be causing this and what is the fix? Is it expensive?