These transmissions are very, very sensitive to fluid conditions. If you have not had a drain-and-fill done on the transmission, I'd do that first. That also could be a fluid level problem.
Now, don't want to upset you, but there is no dipstick for the auto transmission. That's infuriating to me, but it's how it is. Instead, there's an inspection plug and it moves from year to year apparently... well, it doesn't move once the transmission is built, lol, but different years seem to have the fill/inspection plug in different positions.
My advice is to get a good shop to do a drain and fill. VERY important it's done regularly because the filter in this transmission is non-serviceable. It requires literal disassembly of the transmission. Also important not to cheap out on fluid. Use a Mercon LV compatible fluid of good quality. Don't use anything that isn't specifically Mercon LV type.
Get it changed out, and see what you have.