Hi Archana,
To further troubleshoot, consider replicating one of your target entry cells using QuickView to verify why you are not able to enter a number. If every POV selection is at Base, it should accept input unless you have security or potentially constraints on that POV.
UD1, UD2 and Entity might be where the issue is. Check to see if they are at base and you can directly input in that POV through QuickView.
I am guessing your S# is set to accept input but might as well check that too.
Remember - if you reference a DIM in your rows and columns it ignores your POV settings.
Cheers,
A.