Refresh record group to display list of values of documents not created in datablock

I have a form that has a master and detail datablocks,  the detail datablock display more than one record,  which is a tabular information.   The end-user might select from a list of values to add record information, and they can select another information again from the list of values,  but they cannot select a duplicate information already added to the datablock.  They can select information one to many prior to saving the information in the oracle forms.

The form's datablock has a post method in when-new-record-instance trigger:

-- Post information so that record's information just created do not appear in List of Values