kendo-drop-down-list returns incorrect value, but the text is correct

Question

I use a 'kendo-drop-down-list' on my AngularJS application. If a different item is not selected after clicking on the dropdown, (Which means if I click on the same item or click outside of the control) it always returns '1' as the value, but the text remains same. This has a become an interesting puzzle for me after struggling several hours on this and still couldn't understand the root cause behind this.

                            <div class="general-input-wrapper inline-arrangement">
                                <label class="control-label">Type</label>
                                <select id="diaryTypeCombobox" kendo-drop-down-list="diaryTypeCombobox" ng-model="vm.diaryType"
                                        ng-disabled="vm.addNoteOpenFrom == 'OpenCaseDragDrop' || vm.addNoteOpenFrom == 'Organizer'"
                                        k-on-change="vm.valueEffectsOnDiaryTypeChangedByUser()"
                                        k-options="vm.diaryTypeOptions"
                                        k-value-primitive="true"
                                        style="width: 100%;"></select>
                            </div>

The version of Kendo is - 2016.2.714 Browser - Google Chrome Version 62.0.3202.94 (Official Build) (64-bit) OS - Windows 10

Could you please help me to understand the mystery behind this.