What could be the cause of the delay in my period? and the solution?

Need more info: If you are a person whose menstrual cycle is very regular and suddenly it has stopped, we need to think about causes. Oral/IM contraceptives, pregnancy, stress, nutritional deficiencies, weight loss, excessive exercise, eating disorders, excessive weight gain and mental health medications can all cause irregular periods. If any of these fit your situation, small modifications may help. See a DR

Late period: Reasons for missed / late period include: an anovulatory cycle (no egg is released),marked changes in weight; eating disorder; Over-exercising (endurance athletics), stress, travel, significant illnesses, oral contraceptives & other meds, Illegal drug use, breast feeding, hormone imbalances and medical problems (i.e., PCOS). Pregnancy is #1 reason.