Trouble with combining MID and VLOOKUP

My supervisor assigned me a project where I essentially compare two lists. We want to develop a formula that will detect differences between two quotes.

Now this formula [=IF(ISNA(VLOOKUP("*"&MID(D21,2,8)&"*",Email,1,0)),"NOT FOUND","")] works perfectly on the first worksheet, but for some reason it doesn't want to work on the second sheet [=IF(ISNA(VLOOKUP("*"&MID(A7,1,8)&"*",Centre!B18:D45,4,0)),"NOT FOUND","")]. To make things even more perplexing, if I change the MID on the second formula to B7 and reference the product description rather than A7 and reference the SKU, then it starts working as desired.

My bad, what I meant to say is we basically need to see what on the Centre tab is not in the Email tab. So for example, the 332-1286 SKU doesn't appear in the Centre tab, so it needs to say something like "not found" in the Email tab.

Originally Posted by JeteMc

Try pasting this formula into Email!G7:

Formula:

=IF(ISNA(MATCH("*"&MID(A7,1,8)&"*",Centre!D$18:D$45,0)),"NOT FOUND","")

Let me know if you have any questions.

Thanks, works perfectly. I knew I was close.