Cannot refresh Transaction Currency with latest exchange rate

Hi everyone,

In our environment, we have an old exchange rate being set in Nov 2018. Yesterday, a user created a new commitment record, picking up a Transaction Currency with the old exchange rate. When the task has been routed to someone else, he realized that the exchange rate should be updated. And so he did that, creating a new exchange rate, in hope that he can later re-select the currency and the rate refreshes to the newly added. Problem is that when he opened the record again with his edit permission, the Transaction Currency was no longer showing the picker, but