Menu options missing while configuring Autocomplete Rules to pull Grade Rates in Job Requisition

While trying to create a Job based requisition, based on the grade rates assigned to the valid grade for jobs, the values are to be populated in Minimum, Mid & Maximum Salary fields which we've in the requisition.

This is going to be achieved by Autopopulate rules. But even after declaring each of the variable and trying multiple combinations, we are not getting any menu items when we're trying to map the grate rate fields with that of the requisition fields.

How to rectify this error?