?Telogen effvulium(may be Acute or  Chronic) Causes for that somany are there like post fever, nutritional defenciency, physical & mental stress,lack of sleep..etc. Usually it responds well with topical growth factors (peptides) ,   oral hair supplements (biotin,zinc,calcium-penthonate,mg,cu..etc), in case if its not responding.. you can go for the procedures like PRP therapy..to rejuvinate & to stop the hairfall.