A lot of it is shave technique. Blade angle, angle of attack. Skin stretching and the direction of your stroke. Map your face so that you know for sure which direction your beard grows. It took me some weeks to completely finish a shave with my straight razor. I used a Merkur 37C with feather blades for my chin and parts of my neck for weeks or a month or so. Keep at it and you'll find it will get better.