SUMIFS Formula Help

Hello there,

I'm having trouble with an excel SUMIFS Formula that I'd love some assistance with. The formula is using an opportunity ID as the reference.

Problem: When I add up the values using a SUMIFS statement, there are a number of data values that are being incorrectly included - I need to make sure that the sum product leaves these values out.

Goal: Add up the values in the cells of Data Sheet 1 that do not share an Opportunity ID with range A2:A25. AN2:AN is the sum range. B2:B is the reference range that contains Opportunity ID. A2:A25 is the range of Opportunity IDs in Data Sheet 2 that should be left out of the sum product. There are other criteria in the formula that work fine without this clause, so for the sake of this post, I am only including the clause that is causing trouble.

Formula: =SUMIFS('Data Sheet 1'!AN2:AN, 'Data Sheet 1'!$B2:B, "<>"&A2:A25, [Argument 2], [Argument 3], etc.)