SOS! Stroke Tool Problem

Hey

I have problem with stroke tool which counter getting more and more squish when increasing the stroke thickness, does anyone know what happen?

Merciiiiiiiiii
:smiling_face_with_three_hearts:
:smiling_face_with_three_hearts:

Have a read here:

Tl;dr better duplicate the shape and scale it down if you want to have a “perfect” circle.