Error with drop down field in SAIL form

Hi to all,

I'm trying to insert a dropdown field in a sail form using as choiceLabels and choiceValues a multiple constant of type text. But Appian tell me "Interface Definition: Expression evaluation error at function a!dropdownField [line 64]: A dropdown component [label=“Label”] has an invalid value for “choiceValues”. Choice values cannot be null."
I've already tried as documentation say to use the function append and already the function insert, I've tested already to save the value on a Rule Input, but nothing change.

Any suggestions? Before Sail no one ask me for a default value

a!dropdownField(
label: "Label",
labelPosition: "ABOVE",
placeholderLabel: "--- Select a Value ---",
choiceLabels: cons!Date_AM_PM,
choiceValues: cons!Date_AM_PM,
saveInto: {},
validations: {}
)

OriginalPostID-187308

OriginalPostID-187308