Highlighting duplicates based on the date it's under.

dont understand what difference the date part makes
you only want to highlight 1st duplicate
=AND(COUNTIF($A$1:A1,A1)=1,COUNTIF($A$1:$A$1000,A1)>1)
change A1000 to suite your range

on the sheet you have not shown the result required
otherwise can you explain the date part

Hello Etaf,

Thank you for attending to the query. The date part is what I would like to act as the modifier. For instance the number 982060 appears 3 times on the file under cells A2, A3 and A7. Since A2 and A3 are both under the date of 11/02/2019, it will only get highlighted once. A7 will not be highlighted even if it is also the duplicate of 982060 since it falls on a different day. But if let's say A8 is also 982060, one of it will get highlighted since on 12/02/2019 there are also 2 "982606"

Basically, I'm trying to find out the count of unique file numbers per day, should the same number appear but falls on the next day and has no duplicate within that next day, should not be highlighted.

I'm sorry I feel that I'm not explaining it very clearly..

i dont think I understand
can you show various examples of the required output on the sheet and if necessary explain why highlighted

at the moment , I still dont see what difference the date makes]
lets say A2, A3, A7 as is - but an A8 of 982060 on the 12th

so we have 982060 on the sheet 4 times , starting in A2 - A2 gets highlighted
A2 & A3 are for 11th
A7 & A8 are for 12th
A3, A7 & A8 are not highlighted