You can use the entry path described in How do I file Form 8938, Statement of Specified Foreign Financial Assets? for guidance in getting back to where you need to be.
Since the IRS doesn’t provide specific instruction for the scenario you raise in its Instructions for Form 8938 (Rev. November 2021), you’ll just need to return to the Form 8938 area of the program and manipulate the numbers to result in the correct Line 6 amount.
