I can only imagine the amount of effort you have put into resolving the problem of duplicate vendor names when printing checks in QuickBooks Online, mmillecam. Allow me to guide you in the right direction for additional assistance.

Given that you're still encountering the identical problem despite attempting the suggested solutions, my recommendation is to get in touch with our Customer Support team. By doing so, they can conduct a more comprehensive investigation and provide you with guidance on the next actions to be taken. Here's how:

1. Go to the Help icon and choose Search.
2. Click the Contact Us button and enter your concern.
3. Press Continue.

Please note our operating hours so you can contact us timely. For other ways to reach us, refer to this article: QuickBooks Online Support.

If there's a need to review the print setup and align your printer settings, visit this guide: Configure your print settings for printing checks in QuickBooks Online.

The support team will provide more troubleshooting solutions to help address this issue. If you need more assistance managing vendors, add them below. Take care.