How do i get a vector parallel to the surface my projectile just hit?

Hello, my main character can throw a sticky bomb and i want a way to get the vector parallel to the surface it hits (whether it’s the floor or a wall). Right now i have this:

FRotationMatrix::MakeFromZX(HitResult.Normal, CharacterForwardVector).Rotator();

But this only works for the floor and not the walls.

Apparentely this works:

FRotationMatrix::MakeFromZY(HitResult.Normal, CharacterRightVector).Rotator();