Once an audit passes it's deadline you won't be able to submit it. To overcome this you'll need to extend the timeframe first.
From the left-hand menu, click Audits.
Click Audits Planning.
Select the home required from the drop-down box.
Click Audit settings.
Find the required audit then click Setup.
Under the Audit Schedule, click the left blue arrow next to the date picker.
Find the audit, then click Extend or Submit Now.
Click Extend Schedule.
Enter the extend-to date and time.
Click Save.