Before providing any troubleshooting steps, may I ask what mobile device you were using when the app locked up? It can help us get on the same page and provide accurate resolution.
While waiting, you can refresh your data to see the latest available information in QuickBooks Online (QBO). This will also help you retrieve any information about your mileage To do so, follow the steps below:
For iOS:
Go to Settings, then tap General.
Tap iPhone Storage, then tap the QuickBooks Online app.
Tap Offload App.
This will free up the storage without deleting your app's documents and data.
For Android:
Go to Menu then tap More Options ⋮.
Tap Settings then Refresh Data.
Tap YES to confirm.
If you're still having issues with the display, you can uninstall and reinstall the app.
For iOS:
Tap and hold the problematic app’s icon.
When the menu appears, select the Remove App option
Feel free to leave a comment below if you need further help with your mileage or other QuickBooks concerns. I'm always ready to assist you further. Have a good one.
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