Return Text based on Max Sum of number values by month

Hi,
This is for Google Sheets.
I need a formula that returns the text when using a sum max for a number by date.
In the below example, AA02 is the answer for January 2023 b/c 4,120 is the max sum (3,995 + 125).

cell A1 1/31/2023 2/28/2023
Result AA02 CCC

data set
Month Year SKU total
1/31/2023 AA02 3995
1/31/2023 MCT06 100
1/31/2023 AA02 125
1/31/2023 MCT06 125
2/28/2023 AAA 100
2/28/2023 AAA 100
2/28/2023 AAA 100
2/28/2023 BBB 250
2/28/2023 BBB 250
2/28/2023 CCC 900

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