Calculate who has the most repeat calls in the call center

If I understood your requirement...
In D2:
=IF(COUNTIFS($A$1:A2,"<="&INT(A2)+TIME(23,59,59),$A$1:A2,">="&INT(A2),$C$1:C2,C2)>1,"Y","N")

Same concept applies to F & H columns.

Now, for EMPL what should be returned when there are more than 1 that meets condition?
Ex: When there are more than 2 matching result, which of the EMPL should be returned? The original (i.e. earliest call) or one previous? What if original record was found 3 weeks prior? Should it be return EMPL from 2 week prior date, or go all the way back to beginning of record?