How to sum numbers in column which have the same text values in three other columns in excel

I would like to do something like in A20:D28 (with formulas, cause i calculated it manually) with data from A1:F14. Sum amount when NAME and ORDER NUMBER and MONTH are the same values without making duplicates.

I don't want to use PIVOT table (i have a lot data to work with), but if it's needed feel free to help me with it.

Thanks a lotenter image description here