3d print out of shape?

Hi, I’m trying to print this
image

but snapmaker 2 doesn’t print a perfect cylinder. Basically, even if I print the “inside” part at 97%, it still can’t turn inside without so much friction that it’s unworkable. Making the inside part even smaller would make the puzze not work anymore.

Tried on Luban and on Cura with similar issues. Basically the outside shape prints slightly as an oval instead of perfect circle.

I tightened my steel bands and checked my screws. Should work fine… Any hints?