I have experienced that looseness and fixed mine. It was sufficiently long ago that the exact solution evades recollection but those “legs” are what get adjusted. Note that they can be moved in 4 directions: in, out, up, and down. Only one of those tightened the filter. I think it was “down”. What I remember the most is it was the last option I tried. Small changes… good luck.
EDIT: according to this person, the direction to adjust is “out”. His demonstration probably is better to trust than my memory.