Maybe your metabolism is a bit different. Eat 25 g of raw nuts daily, increase your veggies, limit your fruits to one a day only. Increase fibre, decrease all starchy stuff (no potatoes, rice, pasta, bread) or switch to high fibre. Some people just do better on a no fruit, low carb, high protein and veggie diet. This will also keep your blood sugar low and reduces hunger.
Are you sure you need to lose weight? Or could you be restricting calories TOO much? If you don't eat enough, your body will hold onto existing stores of fat - this is called starvation mode - because there's not enough calories coming in.
You might also want to think about getting your thyroid tested. Hypothyroidism is a major cause of weight gain/inability to lose. Additionally, insulin resistance or PCOS can also cause weight gain/inability to lose. For thyroid tests, you should get a minimum of TSH, Free T3 and Free T4.