Hello crosshatchenterp,
Thanks for reaching out to us here. Welcome! It's essential that you're able to accomplish your QuickBooks goals from anywhere. Missing customers in the mobile app is concerning and have a negative impact on your work. I would be happy to help!
When using the mobile app, there are some limitations, as you may have noticed. However, I do suggest refreshing the app. If you experience the same outcome, I recommend uninstalling and reinstalling the app. This is to ensure it's up-to-date. If the issue persists, sign into your QuickBooks Online account using a web browser, such as Firefox, Google Chrome, Edge, or Safari.
If you experience the same outcome, please contact us outside of Community. We'd be happy to look into your situation in more depth, and escalate it for further investigation if necessary.
Feel free to reach back out with any other questions. We would be glad to assist!