Irishcoffee

Drain your auto fluid, consider replacing the ATF filter but can be skipped if on budget as you require the filter + gasket + more fluids.

Use either one:
Lubegard Platinum
Or
k&W Trans X ATF Treatment (blue bottle)

Pour the additives first before New ATF, then top up ATF to cold Max level.

The the car to temperature going through the lower gears/D/N to stop, reverse, rinse repeat for 10 to 20+ minutes to temperature.

Check ATF level, top up to hot Max if needed.
If slight overfilled, let it be, however if overfilled a lot, please drain until at appropriate levels.

I'm no professional, only a fellow slosh box owner that's having your symptoms on a Sentra.

And also slipping clutch plates slosh box on the Iswara.

The 2 ATF additives are my go to solutions.

K&W ATF additive isn't too expensive and very widely available/imported.
give that a shot for high mileage vehicles