1999 Chevy S10 transmission problem

Hello. I'm new here.
My S10 started downshifting at highway speeds when I slightly let up on the throttle. It only starts after driving 20 or 30 miles down the road. (gets hot?) It also hesitates slightly starting from a dead stop as well after that. I dropped the pan, cleaned it up and added new fluid. There was a fine powdery sludge on the magnet in the pan, but no metal shavings. It is still doing the same thing.
It has 95,500 miles on it. 2.2 motor. The fluid was low a couple weeks ago. I added a bottle of conditioner. Don't remember the brand name. 2 reservoirs in the bottle so it mixes as you pour it in. It started acting up 7 days ago.
Any help would be appreciated.
Have a great day.

Hello. I'm new here.
My S10 started downshifting at highway speeds when I slightly let up on the throttle. It only starts after driving 20 or 30 miles down the road. (gets hot?) It also hesitates slightly starting from a dead stop as well after that. I dropped the pan, cleaned it up and added new fluid. There was a fine powdery sludge on the magnet in the pan, but no metal shavings. It is still doing the same thing.
It has 95,500 miles on it. 2.2 motor. The fluid was low a couple weeks ago. I added a bottle of conditioner. Don't remember the brand name. 2 reservoirs in the bottle so it mixes as you pour it in. It started acting up 7 days ago.
Any help would be appreciated.
Have a great day.

Remember dope kills.

Get a good transmission /engine scanner on it and check for codes and problems. and bad sensors/solenoids engine or transmission.
Let us know what you find there.