automate SUMIFS formula in vba code for UNIQUE DATA

This isn't VBA but it does extract unique records based on 3 columns and gives the sum for those unique records.
Insert a helper column (G) and use this formula to concatenate columns A B and C
Enter in G2 and fill down

Formula:

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Use another helper column (I) to extract the unique concatenated values into column I

Formula:

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Enter with Ctrl + Shift + Enter (ARRAY FORMULA)
Enter this formula in K2 and fill across to M2 then down to extract the values of columns A B and C for the unique concatenated values.

Formula:

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For the amounts in column N enter this in N2 and fill down

Formula:

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This is good to row 100 in columns A B and C. If more is needed, change the 100 to whatever you need in the formulae.
In the workbook, the yellow columns can be hidden.