You must post unrealized gain/loss using the Global Process Center global processing prior to resetting the current price of the underlying security of the return leg.
To post unrealized gain/loss:
...
In Accounting Center, in the left navigation pane, click Processing and Exceptions > Global Processes > Unrealized Gain Loss Entries > Post Daily Fund Unrealized Gain Loss-Position.
You see the Post Daily Fund Unrealized Gain Loss-Position panel.Complete the options on the Post Daily Fund Unrealized Gain Loss-Position panel.
Click Submit.
...