Firstsortedvalue with set analysis

[alinesobrinho]

Hi everyone, could someone please help me with this scenario?

I need to sum the values Qty considering the period, so my dataset is like this:

Product	Date	Qty	KEY	Sum	Aggr
1	01/12/2021	93	1|10|20|Text	0	0
1	01/11/2021	93	1|10|20|Text	0	0
1	01/08/2021	279	1|10|20|Text	465	279
2	01/09/2020	93	2|10|20|Text2	0	93

sum measure:

sum(aggr(Sum({$<[Date]={"$(='>=' & AddMonths(MonthStart(max([Date])),-11)& ' <= ' & Date(Max([Date]), 'DD/MM/YYYY'))"}>} Qty),[Key]))

aggr measure:

=sum(aggr(FirstSortedValue(Qty ,-aggr(max(Date),[Key])),[Key]))

The expected result is:

Product	KEY	Sum
1	1|10|20|Text	465
2	2|10|20|Text2	93

thanks in advance