Clearing upload space

Is it possible to clear up space from the uploaded space?

Yes, that is possible. You need to delete the submissions with the attachment file. Here's a guide: https://www.jotform.com/answers/494860-How-To-Delete-Submissions-and-Keep-the-Form

Also, keep in mind that once you have deleted a submission, it is not recoverable. Here's how to download a submissions: https://www.jotform.com/help/73-How-to-Download-Form-Submissions-as-Excel-CSV-PDF

Hope that helps. Thank you.