Losing weight without any problem why. ?

My height 159cms, but my weiget only 44kgs, iam underweight category. My age 26 but iam looking like a school girl because of my thin figure. My parents are looking wedding matches for me, but from groom side not liking me because of my weak and thin figure. i lost 8kg weight, feel very weak and fatigued. blood reports are normal, stool reports are also normal No thyroid... no sugar... no BP... normal hemoglobin My stool are normal(not sticky and not loose) Ultrasound done... stomach scanning done... MRI citi scan done... no problem anywhere i have dark circles under eyes, acne My appetite is very poor, i don't feel urge to eat anything... sneezing issues                                    ⬆ 🔵above mentioned is my total history🔵 My main concern is weight loss if everything is normal then why iam losing weight please.. please.. please.. answer