Bill amount is not the same as the revenue amount

There was some time charged to task 4b on project 11679 in error, so we transferred the time to the correct task on this project.  For some reason, the bill amount for one of the lines of time is double what it should be (see screenshot below); the bill amount should be the same as the revenue amount.  Can this be fixed?  The total bill amount on this task right now should be zero.