I am 18 but my height is not increasing why

How can the height be increased?
We recommend exercising and focusing on stretching and relaxation exercises, and we recommend taking calcium and vitamin D supplements, and paying attention to good nutrition. Zinc supplement like Zicole 20mg can be used once a day. In the event of a growth hormone deficiency, the deficiency is compensated under medical supervision, and after the bone ends are closed, the treatment is done through a surgical procedure By the Ilizarov process to increase height , so we recommend to visit the orthopedics to get proper managment
What is the age to close the bone ends in humans?

• In Females, growth stops at the age of 16-18 years
• In males, it stops at the age of 18-20 years

Diagnosis : 
By taking a medical history, doing a clinical examination, doing a blood test (CBC), measuring the proportion of calcium and vitamin D, checking thyroid gland functions, measuring the proportion of growth hormone, and making x-rays on the bone ends.
Causes : 

• Inheritance from parents
• Genetic diseases
• A natural delay, which occurs in many cases at a young age, as this is a natural delay and the growth stage occurs after a while.
• Malnutrition
• growth hormone deficiency
• hormonal disorders