This is a know burrow bug.
Even saw it live on a streamer before this thread.
Also this is somewhat game breaking and needs a fix ASAP.
@Yoshi or any game dev PM me if you want to know how to replicate the bug.
It's when you get Wraith ultied and you die. When you respawn you also get the disarm debuff from the previous death.
It's a known bug and hasn't been fixed.
Solution: suicide