Adding additional 'IF' statements into a dynamic list formula (Pt:2)

I had some help with the origional formulae here - please see thread for sample workbook etc.

So I have the formula:

=IFERROR(INDEX(Sheet2!A$2:A$1000,SMALL(IF(Sheet2!$Q$2:$Q$1000="UN",ROW(Sheet2!A$2:A$1000)-1),ROW(Sheet2!A1))),"")

which I managed to modify for another use on another tab (on my main file, it bears no references to the sample workbook uploaded) to this:

=IFERROR(INDEX('Sheet2'!AY$2:AY$1000,SMALL(IF('Sheet2'!$AX$2:$AX$1000=$B$3,ROW('Sheet2'!AY$2:AY$1000)-1),ROW('Sheet2'!AY1))),"")

This basically checks if any date in the column AX matches the date in B3, and pulls out those rows.

My new problem, is that I want to add in an additional 'IF' statement, so that as well as checking if the date matches in AX, I want it to check column L and see if data matches a specific text string.

I though just adding an IF(AND(... bit in would work, but it doesn't, so I'm completely stumped...

What I thought I needed:

=IFERROR(INDEX('Sheet2'!AY$2:AY$1000,SMALL(IF(AND('Sheet2'!$AX$2:$AX$1000=$B$3,'Sheet2'!$L$2:$L$1000="chq"),ROW('Sheet2'!AY$2:AY$1000)-1),ROW('Sheet2'!AY1))),"")

Can someone tell me why this doesn't work, and help me achieve what I'm after?

Many thanks in advance.
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