The app isn’t letting me edit or delete a customers details. Can anyone help please?

Welcome to the Community, mike534! I understand how challenging it is when you're unable to perform a specific task in the QuickBooks Online (QBO) app. I'm here to guide you through the troubleshooting process, ensuring you'll successfully manage your customer details with ease.

Based on your description, it appears the issue stems from the data in your mobile app. I recommend clearing the app's data to refresh the system and eliminate outdated files causing the behavior. This will free up the storage without deleting your app's documents and data. 

If you're using an Android device, follow these steps:

1. Go to the More icon at the top right corner of the screen.
2. Choose Settings.
3. Select Refresh Data and choose Yes.

If you're using an iOS device, proceed with the following steps::

1. Go to Settings, then tap General.
2. Hit iPhone Storage and select the QuickBooks Online app.
3. Choose Offload App.

In case the issue persists, I'd recommend uninstalling (tap and hold the app icon) and reinstalling the app. This is to ensure the version you'll be using is updated.

Additionally, while using the QBO app, you can easily monitor the status of your invoices and see if your customers have viewed them. For more detailed guidance, feel free to check out this article: Track invoices in the QuickBooks Online mobile app.

I value your patience regarding this matter, mike534. You can always return here by commenting below if you have clarifications or questions concerning your QBO app. I'll make sure to respond as soon as possible. Wishing you productive and successful business operations!