Bandwitch added package finish very soon

hello I have changed my plan to pro , and I get 400 Gig bandwtich , but I dont know why after finish my 400 Gigs bandwitch , the added pakage that 100Gigs finish very soon and charged day by day , please say the reason of that issue.

You should use Analytics (Netlify or any other, even free ones), to check and see what files are using up your bandwidth.