How to write a accounting rule based on Reason code selected during Item cost adjustment

The offset account should be derived based on the Reason code selected during Item cost adjsutment. I tried creating a mapping set with the cost adjustment reason code, but when I add this into the accounting rule, it is not saving because the reason code is not available in Acquisition cost adjsutment

Then I tried with Reason Name, Description, but nothing works

Please help me how to set the rule for Layer cost Adjustment - based on the reason code selected during item cost adjustment

Thanks, Jay