Hey there, mrkingcasey. I can help you check what's going on with your 2019 mileage.
Since your trial period has ended, the first thing I'd recommend doing is updating your billing information so that the account remains active. If a plan is cancelled, records like mileage can be accessed through the end of our current billing cycle. After that, your data won't be viewable in QuickBooks Self-Employed, but will be kept on file for one year after cancellation. You can resubscribe to gain access.
Once your subscription is reactivated, you can view logged mileage history in the app:
1. Go to your Menu (☰) icon.
2. Select Mileage.
Subscribers can also review their entries when logging in through a web browser. You had mentioned experiencing some issues upon trying to access this way. When encountering these types of problems in a browsing application, I recommend clearing cached data and Intuit-specific cookies initially. That will help your browser function better and does have to be done every now and then.
I've included a resource about mileage tracking which may come in handy moving forward: Automatically track mileage in QBSE
I'll be here to help if there's any other questions. Enjoy the rest of your day!