I have a 2018 Malibu and it's been a great car save for one issue.
Shifting to park will finally the mechanical things, stop car from moving, and show on the dash it's in park.
Turn the car off and I get message "shift to park"
Sometimes lightly moving shifter will fix it sometimes I'm rocking it back and forth so hard the car shakes and I fear I'll break it.

The kicker is a dealer has already swapped the shifter once 2ish years ago but is starting backup again.

GM TSB 19-NA-206
https://static.nhtsa.gov/odi/tsbs/2021/MC-10198852-9999.pdf

I'm not wanting to pay for this fix as its reoccurring and original warranty is gone.

Any tips on moving forward?

If the "shift to park" message isn't cleared it leaves alot of battery functions on and drains the battery so not an option

Call the dealership you had it fixed at and ask them how long they warranty repairs done under warranty. Sometimes that item repaired will be extended for a certain time.

Huh - maybe a GM thing.  Wife’s ‘22 Traverse started doing the same thing about a week ago.  A nudge on the shifter is all it takes at the moment.  She’s taking it in next week.  Be interesting to get scoop on the fix.

I've asked before and 1 year warranty on the fix and it's been 2+ years at this point
I'll call Monday and see what they say




It starts with a nudge and ends in having to either smack the shit out of it or rock it back and forth as hard as you can.
Pretty sure the traverse is included though not sure on years.

ETA the traverse is included in the link in the op but not your year
Maybe a newer version of the TSB has your year listed

Don't know with modern transmissions, but the switch to indicate it's in park may not be in the shifter, it may be in the transmission. Lots of labor expense to pull the tranny to take it apart enough to get to the switch that the dealer doesn't want to do under factory warranty, and not at all under his own warranty cost.

I don't know if this could be part of the problem, but Eric O of South Main Auto fame recently had a guy bring in a newer GM vehicle with electrical problems, steering, trailer brake warnings, etc. ,,, including a shift to park issue.

In this case, it turned out to be the main ground strap (braided) between the body and frame, which had gone green and crusty, and was in the process of disintegrating.

The guy had paid GM 500 bucks to tell him 3900 bucks worth of parts shot from a cannon would fix the electrical problems with his steering and such, but nothing about the shift to park thing.
Once Eric repaired the ground, all the electrical problems the guy had were fixed, including the shift to park issue.

I would dismiss a bad ground somewhere.

Jay

A lot of cars have a shift position sensor. I'd check that.