I can not any longer leave a clients page having sent one invoice without turning I pad off and back on again for each invoice. Unable to contact QuickBooks.

You came into the best place for support, mdannacher.

Let's clear the app's data to refresh the application and eliminate common issues causing the inability to leave a client page to send invoices without turning off your mobile device. Clearing the app's data can be done on the app or on your phone settings.

• For QuickBooks Online app:
  • iOS - Select the menu at the top right and then choose Help & Feedback. Then select Refresh Data and Refresh.
    
     
• In your Phone Settings:
  • 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.

You can refer to this article for additional troubleshooting options to fix issues with mobile apps. This article is a US version but is also applicable to the UK version: Fix common errors in the QuickBooks Online mobile app for Android.

Also, may I know the exact error message on the app? This way I can check if there are special investigations conducted for this.

You might be interested in learning more about accepting mobile invoices in QBO: How to accept mobile invoices: A guide for small businesses.

Feel free to visit this article to find answers to your other QBO mobile questions: QuickBooks Online Mobile app FAQ.

I'm looking forward to hearing from you. Get back to me if any additional questions about managing invoices that may arise. Have a good one.