@Anonymous You can set you gallery items property to sort depending on a boolean variable:
SortByColumns(
tabDaten,
"Ha Missing",
If(
varSortAscending,
Ascending,
Descending
)
)
Then on the sort button OnSelect property you toggle the boolean variable:
Set(varSortAscending, !varSortAscending)
So without setting pressing the sort button the sorting should be descending upon loading at first since varSortAscending will be blank/false.