I applied your 1st formular

=IF(EJ2="",0,INDEX(Sheet2!$B$2:$B$19992,MATCH(EJ2,ROUND(Sheet2!$A$2:$A$19992,2),0)))

Got N/A still .

Using this one

=IF(EJ2="",0,IF(ISNA(MATCH(EJ2,ROUND(Sheet2!$A$2:$A$19992,2),0)),"",INDEX(Sheet2!$B$2:$B$19992,MATCH(EJ2,ROUND(Sheet2!$A$2:$A$19992,2),0))))

As you mentioned not now getting N/A , as you know they are blank .

I can 100% state the numbers mentioned in cols EJ or EK are in sheet 2 .

If i manually change and type in myself in either of these cols where there is a N/A from the Vlookup , the N/A then disappears .