Problems with the cursor. (Fortnite: Battle Royale)

Hello, I play in a Fortnight (PvP) fairly not long ago. About a month probably. Half the time played on an old computer (FPS was under 30, but that's not important). Now
I bought myself a new PC, everything is fine:the picture is smooth, no brakes, BUT I went to the rink and after about two minutes I found my mouse by itself is going somewhere to the left. This phenomenon continues for various amounts of time (sometimes 2 seconds and sometimes gender match). And, as I understand it, the problem is not the mouse, because in all other games, apps, and in General everywhere except the fortnight all right. I even mouse
was turned off during such events, but it goes on. Help pliz.