Save array in rule input

Hello, 

I have editable grid where I'm trying to save all the selections in rule input after that I will use the rule input to push the data to database. The problem is that I'm not able to save the multi drop down as an array when I select more then one option it save only one and not all in the rule input.

Full code below:

                    rows: a!forEach(
                        items: ri!AOS_Documents_Required,
                        expression: a!gridRowLayout(
                          id: fv!index,
                          contents: {
                            a!dropdownField(
                              choiceLabels: {"Option 1", "Option 2", "Option 3", "Option 4",
                                              "Option 5", "Option 6", "Option 7", "Option 8",
                                              "Option 9", "Option 10", "Option 11", "Option 12"},
                              choiceValues: {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12},
                              label: "Dropdown",
                              labelPosition: "ABOVE",
                              placeholder: "--- Select a Value ---",
                              value: fv!item['recordType!{c80b9de7-a15f-41db-8c92-5cb6b7aa7ce3}AOS_Documents_Required.fields.{cc6533a6-0073-472b-a61d-99d1171e7c3a}Region'],
                              saveInto: fv!item['recordType!{c80b9de7-a15f-41db-8c92-5cb6b7aa7ce3}AOS_Documents_Required.fields.{cc6533a6-0073-472b-a61d-99d1171e7c3a}Region'],
                              searchDisplay: "AUTO",
                              validations: {}
                            ),
                            a!dropdownField(
                              choiceLabels: {"Option 1", "Option 2", "Option 3", "Option 4",
                                              "Option 5", "Option 6", "Option 7", "Option 8",
                                              "Option 9", "Option 10", "Option 11", "Option 12"},
                              choiceValues: {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12},
                              label: "Dropdown",
                              labelPosition: "ABOVE",
                              placeholder: "--- Select a Value ---",
                              value: fv!item['recordType!{c80b9de7-a15f-41db-8c92-5cb6b7aa7ce3}AOS_Documents_Required.fields.{5166be0a-f7de-4498-854d-437c347c4372}Country_Template'],
                              saveInto: fv!item['recordType!{c80b9de7-a15f-41db-8c92-5cb6b7aa7ce3}AOS_Documents_Required.fields.{5166be0a-f7de-4498-854d-437c347c4372}Country_Template'],
                              searchDisplay: "AUTO",
                              validations: {}
                            ),
                            a!multipleDropdownField(
                              choiceLabels: {"Option 1", "Option 2", "Option 3", "Option 4",
                                              "Option 5", "Option 6", "Option 7", "Option 8",
                                              "Option 9", "Option 10", "Option 11", "Option 12"},
                              choiceValues: {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12},
                              label: "Dropdown",
                              labelPosition: "ABOVE",
                              placeholder: "--- Select a Value ---",
                              value: fv!item['recordType!{c80b9de7-a15f-41db-8c92-5cb6b7aa7ce3}AOS_Documents_Required.fields.{2e3c19f3-cbac-4d92-a67d-b7d18703a862}SDS_Language'],
                              saveInto: fv!item['recordType!{c80b9de7-a15f-41db-8c92-5cb6b7aa7ce3}AOS_Documents_Required.fields.{2e3c19f3-cbac-4d92-a67d-b7d18703a862}SDS_Language'],
                              searchDisplay: "AUTO",
                              validations: {}
                            ),
                            a!richTextDisplayField(
                              value: a!richTextIcon(
                                icon: "close",
                                link: a!dynamicLink(
                                saveInto : a!save(
                                  ri!AOS_Documents_Required,
                                  remove(ri!AOS_Documents_Required, fv!index)
                                )
                                ),
                                linkStyle: "STANDALONE",
                                color: "NEGATIVE"
                              )
                            )
                          }
                        )
                      ),
                      selectionSaveInto: {},
                      addRowLink: a!dynamicLink(
                        label: "Add new",
                        saveInto: a!save(
                          ri!AOS_Documents_Required,
                          append(
                            ri!AOS_Documents_Required,
                            'recordType!{c80b9de7-a15f-41db-8c92-5cb6b7aa7ce3}AOS_Documents_Required'()
                          )
                        )
                      ),
                      validations: {},
                      shadeAlternateRows: true