Instead of VLOOKUP
use INDEX/MATCH
!
Say your current formula is:
=VLOOKUP(A1,Sheet1!A:C,3,0)
This can be converted to
=INDEX(Sheet1!C:C,MATCH(A1,Sheet1!A:A,0))
It does the same thing (search in A for a match and return the result from column C). Now you can easily get the next match:
=INDEX(Sheet1!C:C,MATCH(A1,Sheet1!A:A,0)+1)
If you want to test if it's still the same employee (in column B), the formula is a bit more complicated:
=IF(INDEX(Sheet1!B:B,MATCH(A1,Sheet1!A:A,0))=INDEX(Sheet1!B:B,MATCH(A1,Sheet1!A:A,0)+1),INDEX(Sheet1!B:B,MATCH(A1,Sheet1!A:A,0)+1),"Only one entry!")