Refund Button Not Working

Version 4 V4 Question
1

I am currently still using V4.1.82.
I have followed the instructions for the Refund tutorial. But when I select the item to refund, the amount does not change to a negative amount.

Refund Item Action
Refund Item Action1228×1308 90.8 KB

Here is my rule for the refund:
Refund Item Rule
Refund Item Rule1300×1351 121 KB

Please help.