I keep experiencing slowness/mining fatigue....

I'm playing Minecraft on Xbox One S which I downloaded from Gamepass. On one survival world I created,  I almost never experience the slowness effect or mining fatigue effect. In another world my wife created she keeps experiencing it on a frequent basis. Not sure that slowness or mining fatigue are exactly what the problem is, but essentially, her character will be mining away after just a few minutes of playing and will be walking very slowly and cannot open doors. Mining is not affected. Jumlijg is not affected. The only cure is to go jump in water. Sometimes it solves the problem for a few minutes, sometimes it solves the problem for a long while. We tried switching it from normal mode to peaceful mode and it is still doing it.