Make sure your horn is properly bound to the skeleton in Unreal Engine. After importing from Blender or Mixamo, the connections between the animation controllers and the bone structure can get lost. Check in the Skeleton Editor that the character’s mesh is displayed correctly and that the appropriate Retarget Options are set. Also, open the Animation Blueprint and make sure the Animation Asset is using the correct skeleton. If the problem persists, try Reimport Skeletal Mesh or use Retarget Manager to adjust the bone structure.