Working hard but still struggling
Most of us are not born to be a know-it-all, "smart", so we work hard.
Working hard isn't studying until 3 or 4 a.m. neither is it spending more than 4 hours to just solve a single math problem each day.
Working hard is knowing what you are capable of doing and doing it in the correct way. In which consists of understanding your own limits, what you know and don't know. Also managing your time wisely, without needing to hassle or "last-minute study" every time you face an upcoming exam.
If you need help, ask for help. Don't wait until the last minute and realize that you have no idea how to solve the math question.
Using the Correct Method to answer a question does not mean that there is only one way to find the solution, but rather it means that there is an easier and faster way.
Studying for hours is not what I would recommend doing. Take breaks in between or even take a nap (by the way, naps are no more than 20 minutes). Let your brain rest, like when you take breaks in a marathon.