Kalita Wave users, when you place the filter into the dripper, do you apply any downward pressure when it touches the bottom? There seems to be quite of flex and room to do so. Compare no pressure on the left, with some pressure on the right:

With most of the kalitas, there is a little ridge on the bottom that holds the filter above the drain holes. If the filter naturally rests a bit higher than that, it's fine and maybe ideal IMO. What you don't want is the filter smashed down on the bottom and restricting drainage. On some kalitas this is more of a problem than others

If I remember, my Kalita 155 had three raised molded raised ridges.