Very often you will have more than one IGC file for each flight. One will be recorded by your main flight computer. But often you will have another one recorded by your phone with SeeYou Navigator or a backup flight recorder.
It would be wrong to automatically include all of these flights in your Logbook. SeeYou will take care of it if you try to add a flight that overlaps with an existing flight in your Logbook.
If you want to change the existing one with another one, you have a simple decision to make:
See how this works in a short video tutorial: