Several times now when syncing my records I have found that the app is unable to do so with limited mobile coverage but full wifi signal - I get an error msg of ‘No connection, try again later’ and the app freezes with no way of leaving that error page to get back into Trap.nz other than re-starting my phone.
You don’t need to restart the phone (though that does work), but you do need to restart the app.
If you are using an Android phone, then you can go to settings, app management, and Force Stop, the app.
And yes, it is a bug, and it has happened to me many times. But in the big scheme of things, it seems pretty minor compared to the information the app actually gives me.