How to reset account usage?

I received an email on the exceeded usage, is there any way to reset the usage as I have edited the form to not allow upload of large files. 

I checked your account and I can see that your upload file space reached the limit of 100 MB for Free account. You need to delete the submissions with attached files to clear the upload file space so you can use your account properly. Keep in mind that deleted submissions is not recoverable.  

I checked your account, your form views and submissions in not yet over limit. You just need to clear your upload file space. 

If you have any questions, please contact us again. Thank you.