Issue with an average based on a specific filter

Hi Imrageth 

With data formated as Table (not mandatory but recommended) named TableOrder:

in F2:

=LET(
  StackAvg, LAMBDA(seed,product,
    LET(
      orders,  FILTER(TableOrder[ORDER ID], TableOrder[PRODUCT]=product),
      also,    IFNA(XMATCH(TableOrder[ORDER ID],orders),0),
      scope,   FILTER(TableOrder[[QNT]:[PRICE]], also),
      VSTACK(seed, ROUND(SUMPRODUCT(CHOOSECOLS(scope,1), CHOOSECOLS(scope,2)) / COUNT(UNIQUE(orders)),2))
    )
  ),
  Products, SORT(UNIQUE(TableOrder[PRODUCT])),
  Averages, REDUCE("AVERAGE",Products, StackAvg),
  HSTACK(VSTACK("PRODUCT",Products), Averages)
)