Conditional Formatting using Formulas as Formatting Criteria

I have a report titled, "Daily Sales Tracker", that has a separare tab for every day of the month. I have created an additional tab titled, "Reps" which pulls info from every daily tab to indicate if a rep worked or not. The info puuled is as follows:
1=Rep Worked
0=Rep Was Off
X or blank=Rep Did Not Report
We need to know when a rep has not worked for 3 consecutive days (0, X, or blank). I am attempting to use conditional formatting to fill those cells that meet that criteria, but have been having trouble doing do. I tried using the following formula:
=NOT(OR(C6=1,D6=1,E6=1))
and applying to to the following area:
=$C$6:$AB$57
but it's not working.

Does anyone have any suggestions on how to get this working?
Thanks!