Sounds like your front band dude.
Try adjusting it, and if that dont do it, you'll need to drop the valve body and take a look at the band. It might have no friction material left.

This is my experience...twice.

When the trans is cold there will be more clearance in the front band so it might not grab and give you second. When it warms up there might be enough to hold the drum.

Might be an adjustment, but most of the time it's already too far gone.

I'm no trans expert like a few I know of on here, so wait for second opinions. All I'm saying is that in both cases it was that damned front band, and I got governor codes as an indication.

In my opinion, that governor solenoid and sensor was the most ignorant thing chrysler ever did.