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  

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?

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: {}
)
}