Ledger Exchange adjustment Not calculated correctly

I would like to share a problem with dynamics AX exchange adjustment function.

Symptoms:
1. You run exchange adjustment in December period (any year)
2. But the result your ledger balance in company currency (MST) / Ledger balance in transaction currency is not equal to the December end exchange rate

Problem:
There is closing transaction exist for the year. Turn out the user run the year end closing (GL>Periodic>Fiscal year close>Opening transaction) prior the exchange adjustment in december  period.

Solutions:
1. Cancel the opening transactions : GL>Periodic>fiscal year close>Opening transaction and set "Balance accounts" to "Reset"

2. Rerun exchange adjustment
3. Rerun the opening transaction, this time choose per normal parameter "Balance accounts" set to "Closing>Opening"

Hope it helps :)

Cheers.