Low iron

Lack of nutrition or physical activity..thyroid problems, depression.

Depression will do that if you have it.

Diet and exercise. And sleeping too much is about as bad as not sleeping enough.

Are u physically active

Maybe you have sleep apnea. That will leave you always tired.

because you are deeply depressed.

not kidding - was the same and found out i had low testosterone and low thyroid. doctors in the USA fundamentally misunderstand hormone issues and prescribe antidepressants instead. get your hormones checked out