Store the values of a multipledropdownfield

Try using the below code

{
    a!multipleDropdownField(
      label: "Acceso a servicios basicos?",
      labelPosition: "ABOVE",
      placeholder: "--- Seleccione ---",
      choiceLabels: { "Agua", "Luz", "Teléfono", "Internet" },
      choiceValues: { "Agua", "Luz", "Teléfono", "Internet" },
      value: if(
        a!isNullOrEmpty(ri!CWA_OECClient.coecaccesoservicionbasicos),
        null,
        split(ri!CWA_OECClient.coecaccesoservicionbasicos, ";")
      ),
      saveInto: {
        ri!CWA_OECClient.coecaccesoservicionbasicos,
        a!save(ri!CWA_OECClient.coecaccesoservicionbasicos, joinarray(ri!CWA_OECClient.coecaccesoservicionbasicos, ";"))
      },
      required: true,
      validations: {}
    )
  }

i tried it, but doesn't work  

i tried it, but doesn't work  

Could you please show us the rule imput CDT

Yes, thanks so much

these are?

For Me, It is working fine.

 if i pick only value, it works great 

If i pick or select TWO or more values, an ERROR appears (see the image bellow)

Could you please use trim over the split function please?

this part?

{
a!multipleDropdownField(
label: "Acceso a servicios basicos?",
labelPosition: "ABOVE",
placeholder: "--- Seleccione ---",
choiceLabels: { "Agua", "Luz", "Teléfono", "Internet" },
choiceValues: { "Agua", "Luz", "Teléfono", "Internet" },
value: if(
a!isNullOrEmpty(ri!CWA_OECClient.coecaccesoservicionbasicos),
null,
split(ri!CWA_OECClient.coecaccesoservicionbasicos, ";")
),
saveInto: {
ri!CWA_OECClient.coecaccesoservicionbasicos,
a!save(ri!CWA_OECClient.coecaccesoservicionbasicos, joinarray(ri!CWA_OECClient.coecaccesoservicionbasicos, ";"))
},
required: true,
validations: {}
)
}