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The formula that you have for Column 1 produces a text string, not a date/time object.
The DATETIME_FORMAT
function expects a date/time object, not a text string.
Option 1:
You can turn the value from Column 1 back into a datetime object by using DATETIME_PARSE
.
DATETIME_FORMAT(DATETIME_PARSE({Column 1}, 'DD/MM/YYYY'))
Option 2:
You can go use the same basic formula as for Column 1, but change the format options.
DATETIME_FORMAT(SET_TIMEZONE(CREATED_TIME(),'America/Sao_Paulo'), 'MM/YYYY')