Almost as soon as I start a cross country skiing activity now it pauses (as of February 2025). And never automatically resumes even though it shows speed.
Apparently this was a problem in earlier years as well without a resolution to the problem (thread is locked so I can't post this there): https://forums.garmin.com/sports-fitness/running-multisport/f/forerunner-255-series/360251/ski-activity-immediately-pauses
I think I have a solution. Go into the settings for skiing (press and hold the up button while you are in an active skiing activity), and turn ON one of the Auto Pause settings (I did the speed settling). Then turn it OFF again. That seemed to reset the immediate pause for me.
My hunch is that constantly hitting the start/stop button with the back of my hand during cross country skiing (which I never do running) may have triggered the setting.