Allergy and going to puzle. What to do?

She was also very strees that why her all nurves became drying in a small amount  and facing vocal cord issue she stared coughing when she  start talking ..i see some ent doctors they only told to relax mind..everything will ok..and then .she started sneezing before 5 months...from the time..she regularly sneeze 3 to 4 in a day..with runny nose...i wanted to identify her allergen so one day i  am cleaning my hall there was so much dust but when she was stand there for5 hours she didnot sneeze at all..she eat all foods..no burden...but her immunity was very weak..so i want to know that can weak immunity cause allergy... extremely weak..catch cold very quickly and and what should i do to avoid it...it was very annoying...no dust allergy, no food allergy...what should i do...i think she also have vitamin d deficiency because in 8 months she didnot going outside home because of lockdown...her bones are cracking often..so calcuim deficiency but she eat so much calcium in her diet.what to do