Mobile app invoicing freezes when updating invoice and creates duplicate invoicing.

We can perform troubleshooting steps to help fix the issue in your mobile app, ksmall24. 

When the application is not fully functional, it's recommended to clear its cache files. This is a helpful initial step to resolve any sort of errors.

Follow these steps if you're using an iOS device: 

1. Select the menu at the top right and then choose Help & Feedback. 
2. Click Refresh Data and Refresh. 

For Android devices: 

1. Select the menu at the top right and choose Settings. 
2. Press Refresh Data and choose Yes.

In your Phone Settings: 

• Android - From your phone's settings, select Apps (varies by device). Choose the QuickBooks app from the list and select Storage. Select clear data. 

• iOS - From your phone's settings, select Settings, then, click on General and choose iPhone Storage. Select an app that's taking up a lot of space. To free up the storage without deleting the documents and data for the app, select Offload App. 

Once refreshed, restart your mobile phone, and check if you'll be able to work with your mobile app. 

Just in case the issue persists, uninstall and reinstall the QuickBooks Online mobile app. Let me share this article with you for additional reference: Mobile App FAQs.

You can always leave your comments here if you have follow-up questions with the mobile app. I'm always here to help you out. Take care!