Welcome to the Community space, jpf_15-hotmail-c.

A possible cache or outdated app might be the reason why your data is not showing up in the mobile application. I'd like to recommend some steps to help you fix the issue. 

Let's start by making sure that your QuickBooks Online app for iOS or Android is updated. Then, close and re-open the app and try to check if the data is displayed.

Otherwise, we can try clearing the app's data to refresh the application settings

In the QuickBooks Online app:

• Android - Tap the menu at the top right and choose Settings. Then select Refresh Data and choose Yes.
• iOS - Tap the menu at the top right and then choose Help & Feedback. Then select Refresh Data and Refresh.

In your Phone Settings:

• Android - From your phone's settings, tap Apps (varies by device). Choose the QuickBooks app from the list and select Storage. Select clear data.
• iOS - From your phone's settings, tap 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 done, restart the application and sign in to your account. Check to see if the data is available.

In case you encounter some errors, you can check out the solutions in this article: Fix common errors in the QuickBooks Online mobile app for Android.

Please keep me posted on how it goes. I'll be around to help you out some more. Take care and stay safe.