HELP!

I have literally tried everything to lose weight. I'm in a daily calorie deficit, eating a bit healthier, walking more and doing physical activity, and yet no weight loss. I don't know what to do anymore. I've been trying for over 3 years to lose weight, I've lost only 20lbs total. D: I started at almost 250, I'm currently 222-226 (it flucuates).

Lately I feel super sick, my stomach is always bloated, etc and I have no clue why. I do know I have PCOS but still, I should be losing something!

HELP!