If the problem persists after checking the shift cable as suggested above, my guess is the condition could be caused by clutch failure.
I'm a newcomer to side by sides. I owned a 2020 Talon for a few months and only about 300 miles last year and now a 2021 Pioneer 1000 for about three or four months and 200 miles so I have less experience with the Honda DCT than almost everyone on the forum but I'm an "old car" guy who has been reading about and operating cars, trucks, rvs, motorcycles, and boats since the 1940s.
I'm a big fan of DCT transmissions. A true believer. But I know they can be damaged by applying power against an immovable load. What I mean is attempting climb over a fallen tree truck, large rock, or other large object by applying heavy throttle for an extended period of time when your buggy is unable to move. It would be called slipping the clutch if done with a manual transmission. That particular practice causes excessive friction, overheating of transmission fluid, and rapid wear of the clutches.
I haven't seen the issue or the result discussed here and don't know if it's common.
I owned a Volkswagen Jetta wagon with the turbodiesel TDI engine and DCT transmission. The owners manual warned against allowing the car to strain against a load with heavy throttle. The VW DCT and Honda DCT are not identical but I'm sure their design is very similar.
A DCT is basically two small mechanical gear trains, one above or beside the other, each mounted behind a tiny computer controlled clutch. One of the mini-transmissions contains gears 1-3-5 and the other contains gears 2-4-6.
When the vehicle is stopped, the computer selects gear #1 and when throttle is applied the computer begins engagemen of the mini-clutch for that gear.
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