If a simple reboot of your Mac doesn’t fix things, see if the problem still happens in Safe mode (press and hold the shift key down at startup). It can take much longer to safe boot (5 min) so be patient.
How to use safe mode on your Mac - Apple Support
Safe mode is non-destructive to user data. It’s not a cure-all, but very often corrects weird software behavior by forcing the OS to do cache clearing and other housekeeping. When you're in safe boot, the machine will not be at its best performance, especially with graphics, but that's expected.
Often not required, but consider allowing the Mac to "soak" in Safe mode for an hour to allow maintenance routines and processes time to complete, then exit safe mode by restarting your Mac normally and re-evaluate the issue again.
Does the problem persist while in Safe mode?
Also -
> Ensure the trackpad is clean. Use a damp cloth - not wet - to wipe any oils or grime from the surface.
> Go to System Preferences > Trackpad and disable that swipe gesture. Then restart the Mac, return to System Preferences and re-enable the gesture. Sometimes that will reset a thing.
Finally, trackpad gestures continue to be completely functional in the macOS, including in the newest macOS 14 Sonoma. So don't let the fear of losing this awesome feature deter you from upgrading your software or even your hardware. 🙂👍🏽