If you don't include the third (optional) parameter in a MATCH formula, then the function will not look for an exact match - it will match on a value that is less than or equal to the sought item. For this to work properly, the data in the match_range needs to be sorted, and I can see that yours isn't, so this can produce spurious results. The solution is to look for exact matches, which means changing expressions like this: MATCH(A17,Internships!A:A) to this: MATCH(A17,Internships!A:A,0).

The 0 could be replaced by FALSE, but I use it as it is quicker to type and means the same.

Hope this helps.

Pete