Hello nancyp,
Thanks for reaching out to us here. It's vital you're able to use the mileage tracking feature so you can bring your finances into perspective using QuickBooks. I'll be happy to share more info so you're on the right track.
In order to successfully track the mileage, you'll need to have the app running in the background. I recommend checking to see you have the app running while traveling. I also recommend troubleshooting this issue using the following article that shows you how to: Fix mileage tracking issues in the QuickBooks Online mobile app.
Let me know if you have other questions. I'll be on standby.
