ChangeTimeStamp not working

I have created a checks and balances form where one person completes a task and the second person has to verify completion. I want to have two change timestamp columns, one bound to barcode1 and one bound to barcode2. when barcode1 changes, it does input a time but I also have the initial value set at now(). When the second person scans their barcode, nothing appears in the changetimestamp2 column.

I have tried changing the first column to a dateTime field thinking maybe you cannot have more than one change timestamp field (I do not believe this to be true).

But something isn’t adding up here. Any help?