I want to export from my IR in xlsx format but there’s something different about displaying date columns in excel and IR.

I’ve set this code in Database Session to show all dates in APEX application based on Persian calendar :

BEGIN
 EXECUTE immediate 'ALTER SESSION SET NLS_CALENDAR=PERSIAN';
EXECUTE immediate 'ALTER SESSION SET NLS_DATE_FORMAT=''YYYY/MM/DD''';
END;

It works correctly but when I export from IR in xlsx format , I see my data columns are displaying based on GREGORIAN calendar.

but it works fine in csv format and all dates are showing on exact NLS_CALENDAR that I’ve set on app.

I’ve tried to_char(date_column,'yyyy/mm/dd','nls_calendar=persian') but I want to know why this happens only in xlsx format ?