Steps counted when rocking in a chair

I have a La Z Boy recliner that I frequently use to rock in and I noticed that my watch is registering every rock as a step. On a day when I should have had about 6k steps, it registered 19k. I currently have the Ultra and I’m considering returning it.

I read somewhere that I can calibrate it and that may work, but I own a Garmin Fenix and I’ve never had this issue. In fact the Garmin is incredibly accurate and in the two years that I’ve owned it, it’s never once registered the rocking as footsteps. How can Garmin figure it out but not Apple?

I’d just like some feedback before I rush to conclusions and return it.