Threshold Based Approvals - EPBCS

Summary: I have set up one workflow with simple Threshold base approval. however it's not working. I have gone through the Oracle demo and all seems to be same except Oracle has used a secondary dimension in the planning unit and the conditions are slightly different in my case.

But still not able to make it work.

Here is my requirement:

I have two reviewer X and Y and I have set up two condition on the form using validation.

Rule <=20 condition : If the expense is less than or equal to 20 then the approval should go to X only and skip Y