I will ask an admin to review this. Please take note that your storage must be about 75% full already. The files in your account must pertain to your account, they cannot be backups of your files or databases, and they must comply with the terms of service. You can get multiple increases, but the same rules apply each time. Please clear up anything in your account that might not fit these requirements before an admin looks at it, and if there is something unusual be prepared to explain what it is.
I've flagged this for admin review. You should see a response in a day or so.