Because the phone is out of power and leaves the application, reconnect the application and enter the unfinished game. At the end, fif file only contains the data before disconnecting. However, the heart rate data and power data displayed in zwift are complete, while the fif file shows that only 23 kilometers before the application is disconnected，But I finished 138。
When Zwift crashes, the fitfile it saves is often incomplete or partially corrupt.
Sometimes I am able to recover the file by putting it through the “corrupt time fixer” tool here - https://www.fitfiletools.com/#/ctf#view
Sometimes it fixes it, sometimes it doesn’t. That works if you just want to manually upload the file to strava or other platform but there’s no way of correcting the info in zwift or zwiftpower that I know of.