Could not display interface. Please check definition and inputs.Interface Definition: Expression evaluation error at function a!forEach [line 438]: Error in a!forEach() expression during iteration 3: Expression evaluation error at function a!dropdownField

Hi Everyone,

We have a editable grid where we placed 2 drop down values. Second dropdown choice values and choice labels purely dependent on first drop down selected value.But we are getting the error.

a!dropdownField(
                                    label: "Therapeutic Area",
                                    placeholder: "---Please Select---",
                                    choiceLabels: index(local!therapeuticArea, "name", {}),
                                    choiceValues: index(
                                      local!therapeuticArea,
                                      "therapeuticAreaId",
                                      {}
                                    ),
                                    value: fv!item.therapeuticAreaId,
                                    saveInto: {
                                      fv!item.therapeuticAreaId,
                                      a!save(fv!item.diseaseStateId, null),
                                      a!save(fv!item.studyGap1Id, null())
                                    },
                                    required: true(),
                                    validationGroup: cons!ISR_VALIDATION_GROUP_SUBMIT
                                  ),

a!dropdownField(
                                    label: "Evidence Category",
                                    labelPosition: "ABOVE",
                                    value: fv!item.studyGap1Id,
                                    choiceValues: index(
                                      rule!ISR_qry_GetStudyGap1ById(
                                        isActiv: true(),
                                        studyGap1Ids: rule!ISR_qry_GetStudyGap1ByTAIds(
                                          therapeuticIds: fv!item.therapeuticAreaId,
                                          diseaseStateIds: fv!item.diseaseStateId,
                                          fetchTotalCount: false()
                                        ),
                                        columns: { "name", "studyGap1Id" },
                                        returnDataSubset: false()
                                      ),
                                      "studyGap1Id",
                                      {}
                                    ),
                                    choiceLabels: index(
                                      rule!ISR_qry_GetStudyGap1ById(
                                        isActiv: true(),
                                        studyGap1Ids: rule!ISR_qry_GetStudyGap1ByTAIds(
                                          therapeuticIds: fv!item.therapeuticAreaId,
                                          diseaseStateIds: fv!item.diseaseStateId,
                                          fetchTotalCount: false()
                                        ),
                                        columns: { "name", "studyGap1Id" },
                                        returnDataSubset: false()
                                      ),
                                      "name",
                                      {}
                                    ),
                                    placeholder: "-- Please Select the value for Evidence Category",
                                    required: true(),
                                    disabled: if(fv!item.therapeuticAreaId, false, true),
                                    validationGroup: cons!ISR_VALIDATION_GROUP_SUBMIT,
                                    saveInto: {
                                      fv!item.studyGap1Id,
                                      a!save(
                                        fv!item.studyGap1Name,
                                        index(
                                          rule!ISR_qry_GetStudyGap1(StudyGap1Id: fv!item.studyGap1Id),
                                          "name",
                                          null
                                        )
                                      ),
                                      a!save(
                                        fv!item.evidenceCategory,
                                        index(
                                          rule!ISR_qry_GetStudyGap1(StudyGap1Id: fv!item.studyGap1Id),
                                          "name",
                                          null
                                        )
                                      )/

                                    },
                                     

                                  ),