Is it consistently reproducible? Android or iOS? What version? Any other information?
To reproduce it, the airplane mode must be activated and then the Traccar Manager must be started. Often "Failed to fetch" appears, but also very often net::ERR_INTERNET_DISCONNECTED. In this case, the only solution is to reinstall the app. I have Android 14 installed.
Can you please do a screen recording. It's hard to believe that restarting the app and clearing the cache doesn't help.
Traccar Manager does not display any content after a brief loss of internet connection.
Clearing the cache does not help, only uninstalling/reinstalling of the app helps.
Unfortunately, there is no refresh button in the app or that the content is refreshed when the screen is pulled down...