We still have the Reference no. field on the Expense, slonero.
Let's try refreshing the page by pressing F5 in the keyboard. If it still didn't show up, we can do a few browser troubleshooting steps and see if the issue is caused by stored cache files. They can sometimes cause unusual behavior within QuickBooks.

We can log out and log back in using a private browser since they don'ts store any history and cache. Let's create an Expense afterwards and see if the Ref no. field now shows up. If it looks fine, we can switch back to our main browser to remove the cache files. Another way to get rid of the unexpected behavior is by using a different browser since they too have different cache folders. We can use Google Chrome, Internet Explorer, or Mozilla Firefox.
Once everything looks good we might want to track our expenses by running vendor reports. Just click the Reports menu and scroll down to the Expense and Vendors section.
Keep me posted on how this works. I'll be around to help. Keep safe!