Hello, Joos.
Let me provide some troubleshooting steps to help you fix your QuickBooks Online app.
Too much cache on any application, such as QuickBooks Online, can cause malfunctions inside the app. That's why you can't see the option to contact our support. We'll have to reset the app to ensure your QBO app works properly.
For iOS:
- Go to your phone's settings.
- Select General, then choose iPhone Storage.
- Tap QuickBooks Online from the application list.
- Select Offload App to free up the storage without deleting the documents and data for the app.
Moreover, I also recommend uninstalling and reinstalling the app. Alternatively, you can use the mobile browser to view your customers list.
If the issue persists after performing all the recommended fix above, I'd suggest contacting our QuickBooks Online Support Team to create a ticket for product investigation. This way, you'll get to inform our product engineers about the issue and generate a fix as soon as possible. You'll also get a notification via email for updates once the issue gets resolved.
Additionally, you may want to enhance your business communication in terms of personalizing your sales forms. Feel free to read this article: Customize invoices, estimates, and sales receipts in QuickBooks Online.
If you have any further questions, you can leave a comment below. I'm always available to assist you. Have a great day!
