Fortnite A button not working?

I have the following problem: In Fortnite the key with which you do not jump works with me, i.e. The A key. (Xbox one) I try to jump by pressing the button it doesn't work. Restarting the pc doesn't work, don't try it now. How do I fix this problem? I ask for the fastest possible answers: Joni1597

So I would think of two things now:

does the A key work on others? If not, your controller probably has one.
If your controller works normally in other games, then look in the settings for the key assignment to see whether jumping is also set to A. I don't know why the key assignment should change just like that, but I can take a look.

hope i could help have a nice day

Thanks, helped