Anyone else’s app playing up not sending invoices just loads on preview page

Welcome to the QuickBooks Community, Dhjcooling. Wishing that you're doing great. Let me go ahead and assist in sending your invoices.

There are several ways for your invoice to be un-stuck on the preview page. First, update to the newer QuickBooks Mobile app version. Second, clear the QuickBooks App data.

Here's how: 
 

1. Open Settings.
2. Tap on Apps.
3. Tap on the app you want to clear data for (QuickBooks Accounting).
4. Tap on Storage.
5. Tap on Clear Data.
6. Tap on OK to confirm.

And lastly, we can uninstall and then reinstall your app. This step will give you a fresh start on your QuickBooks Mobile app.

I'll attach some articles that can assist you with your invoice on QuickBooks Online: 

•  Fix common errors in the QuickBooks Online mobile app for Android
• Customize invoices on the QuickBooks Online mobile app 
• Receive an invoice payment using the QuickBooks Online mobile app 

If you still have other questions about your receipt. You can reply on the thread or create a new post. Take care and have a great day!