Hi and welcome to HCM From what I understand , undri is the term for alopecia areata where the hair is lost in clear patches due to an immune reaction in the body against your hair. Did you consult a dermatologist last time? Certain infection can cause loss of hair but you would also have other skin symptoms in that area. Did the previous hair lost grow back? If it is just unexplained loss of hair in patches and repeating, it s mostly alopecia areata. Do you have any other illnesses or allergic conditions? Or family history of similar complaints? You can use a minoxidil 5% solution at night on the area for a month and observe with hair supplements such as as Keraglo men capsules daily. You can also try steroid creams to stop the progress. But these methods take time. I would advise you to consult a dermatologist to confirm the diagnosis and start steroid injection in the area which gives good results. Other options can also be discussed. keep in mind that they can recur in other areas again or sometimes regrow on its own and recover. Also check if you experience hair loss anywhere else on body. Hope this helps.