Grid Snapping changes the stem width when I move the bezier points at the end of the stem

Hi everyone. I recently download the app and I’ve being having trouble with grid snapping. I have some drawings where the end of the stems hace angles. If I try to short the stem by moving the bezier points at the end of the stem, the stem width changes. Haw Can I disable grid snapping? Is there is any way I can move the stem points maintaining its. width?