Over 500mb of your usage appears to be backups. Backups should be downloaded to your local computer for safe keeping.
Having backups on the service will not help at all if said service fails. From what I can see you also have two backup plugins that both may be active (one uses roughly 370mb an the other roughly 170mb).
This means that most of the usage is not directly related to your website, so the increase is denied at this time.