First, make an archive and give it todays date.  Do not remove old data this time.

How to find lost punch data in a TimeSource or Icon TimeVue.

Look in the "Poll Log".  It will show all the times you polled the punch data from the clock.  Find the one that would have the date range you are missing.  Select
"View".  It's kinda packed in - it's for the software, not for human eyes - but you will be able to see the date, employee number, and punch times.  Double-check that that information is not in the employees punch list.  Once you've found the missing punches, select Re-Import Punches.  You will get a warning about Duplicate Punches.  Accept it, and import the punches.  Tell it to APPEND TO EXISTING DATA (if prompted).  Do not replace existing data, you'll lose your current payroll punch records.

Get your reports by setting up a custom report date frame.

If, after you have done this, you want to restore it back to the pre-appended state, just select RESTORE, find today's Archive, and tell it to OVERWRITE EXISTING DATA".  That is your backup, your "life-line".