Dear Sir,
I totally understand your frustration about the inability to increase your weight even though you are taking supplements and going to gym.
The answer to your question is easy : Increase your calories intake. Even if you think you are eating enough calories, the fact that you are not gaining weight means you re not getting enough.
Some tips are helpful in your case:
1- Eat around 6 meals a day. You will be able to eat smaller amount of food with each meal however your total daily calorie intake will be higher and you will be able to keep your body in an anabolic state.
2- Track your calories. you can calculate the amount of calories you are eating daily to make sure you are getting enough food. You have to calculate your
basal metabolic rate and your total energy consumed based on your age, lifestyle, weight, height and sex. There are many free calculators online that can give you these numbers. You must increase your calories by around 500 kilocalories above the amount of energy consumed. then you will be able to increase your weight ina healthy fashion.
3- The most important point is always to eat healty food. You will need more time to increase your weight with healthy food, however you will increase mainly muscle mass due to the fact that you go to gym.
4- Eat healthy calories dense food. Lists of these food are availble online.
5- Dedication to gym and diet will give you the results you want. The good point about being ectomorph is that they have good
insulin sensitivity, and insulin is anabolic, so they can increase muscle mass better than endomorph and mesomorph body types. However it might seem harder but it is doable.
Best regards