Try these steps to help your applicants prevent a timeout. 

1. In Account Designer ensure "Timeout Settings" are enabled. We suggest 45 minutes for "Idle Minutes"  and 60 minutes for "Timeout Minutes". The Idle warning text should contain a message informing users they are about to loose all work. We suggest something similar to "You are about to be signed out please SAVE and CONTINUE LATER to keep your work". The Timeout Text should have a message communicating "Due to inactivity you have been signed out without your information being saved"

You can get to Account Designer from your dashboard clicking LAUNCH > APPLICATIONS > FORMS MANAGER > SETTINGS > ACCOUNT DESIGNER

2. Add messages for applicants to Save frequently and email drafts to themselves before submitting in the application page instructions in the Page instructions and on the sign in page.