Over last 2 months, no sugar, alcohol, coffee, limited carbs, diary, small portions. increased exercise to 30 minutes per day. no weight loss yet. why?

Depends: Could be a thyroid or other medical condition, so see a doctor to get this evaluated. Also depends on your net total daily calorie intake. If calorie intake is less than calories burned on a daily basis, over time you should lose weight. Some people who exercise, end up eating more calories, evening out the net total calories per day, so no weight loss . I recommend myfitnesspal.Com website or app.