Not able to default and get the options on oj-select-one

Content

We have a requirement to display list of values once it is saved, need to retrive and provide the option to update it.
seperationApprovalSignedByName is assigned on the load of the page.
Have set filterCriterion for mIREmployeeDetailsBOListSDP
{
 "op": "$co",
 "attribute": "displayName",
 "value": "{{ $variables.Separationapproval.seperationApprovalSignedByName }}"
}

<oj-select-one label-hint="[[ $application.translations.app.select_one_label_hint_9fab ]]"
   value-option.value="{{ $variables.Separationapproval.seperationApprovalSignedByName }}"
   options="[[$page.variables.mIREmployeeDetailsBOListSDP]]" options-keys.value="displayName"
   options-keys.label="displayName" on-value-changed="[[$listeners.ojSelectOneValue2]]"
   value="{{ $variables.Separationapproval.seperationApprovalSignedByName }}">
</oj-select-one>

Not able to get values other than the one stored at the first time when tried to update. Please suggest the way to display all the values and default the existing value stored.