Hi there, 023046560421814,
The name of the vendor in the Mailing address box is default. And, there isn't an option to remove it. This will keep coming back even if you delete it in the field.
Explore what's new and coming through the Product Updates link. Just navigate by clicking the specific topic on this page for more details.
Feel free to read through this article, Vendors overview for other tasks you can do on the Vendor page.
Thanks for posting here in the QuickBooks Community. Let me know if there's anything else you need. I'm always around to help you out.