Hair fall problem. What should i do?

Hello My age is 27 year male , last year I visited dermatologist for thinning hair , my hair just started thining and pattern baldness , but still I had good amount of hair volume , I never faced hair fall in my life , so doctor advice me hair4u serum and few multivitamin , I used a 3 months then doctor change serum minichck . I used that serum for 20 days and suddenly hairfall starting within a week hairfall approx 200 hair per day , I visited my department dermatologist , he says everything okay hairfall stop after 3 months no treatment needed . Even after my 6 months my hairfall no stopped then I admitted hospital for High fever approx 10 days when I came back from hospital , I feel weakness but my hairfall stopped completely , 3 month no hairfall. But a month ago my hairfall starting again 250 per day approx , still my department doctor says no treatment needed , it will be fine after 3 months , I don't know I am confused , I lost half of my hair density .what should I do ?