The Community has you covered, @funnygirl238. I'll help you get that information added to checks.

When creating a check, it'll autofill the vendor's mailing address: name, company name, and address. Once saved, you'll be able to print it with the information. It's possible this could have something to do with your browser. We can perform basic troubleshooting to isolate the issue.

Let's try accessing your account through an incognito window to rule out the possibility of a webpage issue. You can refer to these shortcut keys to open an incognito window in all supported browsers:
 

• Chrome: Ctrl+Shift+N
• Firefox: Ctrl+Shift+P
• Safari: Command+Shift+N

Log in to your account and create a test check. If the mailing address appears, you may have accumulated too much historical data in your browser. I'd recommend clearing its cache so you can access QuickBooks with a clean slate. You can also use a different supported browser.

Moreover, you'll want to edit the check and manually enter the necessary info in the Mailing address text box. Here's a screenshot for your reference:

Please let me know if you continue to have issues. I'll be here every step of the way. You can reach out to the Community any time you need a helping hand. Take care!