How to post difference expense account for depreciation in difference ledger?

Dear Expert,

In our system we have two ledger and two depreciation area. One is for 0L, the other is for 2L

Then I create account determination and set difference expense account for depreciation in depreciation area 1 & 2

When I used AFAB to do depreciation posting test run, the expense account for depreciation is not difference.

My step is :

a) create account determination

b) AO90 set account for account determination

c) OAOA create new asset class

Which step do I have missed? How can I let the difference expense account post in difference ledger?

Best regards,

Eric