Fortnite bug while running, what can you do about it?

Games on the switch fortnite, sprinting has not worked properly for 2/3 days. I've tried a few things and it didn't work. The problem is that I can sprint but then suddenly I stop or run normally although I move the joy con all the way forward, I stop. I've already screwed around the dead zone of the controller. Recalibrated and none of it works anyway

Automatically sprint off and on again