What is going on when the acacia bird tail hair is falling

Acacia Bird's Tail is changing hair.This kind of bird usually changes twice a year. The first time is in the summer, and the second time is about 20 days before the winter changes.Be sure to keep the hygiene in the cage while changing the hair, and clean it every day to prevent the birds from getting sick.At the same time, don't take a bath often, it is easier to get cold after no hair.Also pay attention to feeding.