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How to find customer name with highest sales and the total

For customers with the highest total sales transaction:

Control+shift+enter, not just enter, and copy down:

=IFERROR(INDEX($F$2:$F$30,SMALL(IF($A$2:$A$30=MAX($A$2:$A$30),ROW($F$2:$F$30)-ROW($F$2)+1),ROWS($H$2:H2))),"")

For customers with the highest total of total sales transactions:

First, in G2 enter and copy down...

=IF(ISNA(MATCH(F2,$F$1:F1,0)),SUMIFS($A$2:$A$30,$F$2:$F$30,F2),"")

then in I2 control+shift+enter, not just enter, and copy down:

=IFERROR(INDEX($F$2:$F$30,SMALL(IF($G$2:$G$30=MAX($G$2:$G$30),ROW($G$2:$G$30)-ROW($G$2)+1),ROWS($I$2:I2))),"")