Calc - WEEKDAY function - read day, month and year from cells

I’m trying to use the weekday function to read the date from specific cells. Say I have the day in A1, the month in A2 and year in A3. The function would be something like:
WEEKDAY(“A1/A2/A3”, 2)
And it should be the same as WEEKDAY(“1/11/2021”, 2).
But for some reason it doesn’t work. I suspect it’s because of the " " but I’m not sure of that, or what is the correct formatting.

"A1/A2/A3" is a string and nothing else,

A1/A2/A3 is the Division 1 / 11 / 2021 and close to zero.

“1/11/2021” is not a date.

=WEEKDAY(DATE(A3;A2;A1);2)

Possible duplicate of LibreOffice Calc WEEKDAY() function

No it isnt!