How do I add a 1099 for a vendor that already has "track for 1099" on, has >$600 in chk payments & whose payments are in the same account as another vendo that does show?

I'll guide you on how to add a vendor so it shows up on the accounts for 1099, Consultant.

Aside from tracking the vendor for 1099, you'll have to make sure that you've selected the correct account for the name of the vendor to show up on the list. To do so, follow the steps below:

1. Go to the Payroll menu, then select Contractors.
2. Click Prepare 1099s.
3. Select Confirm information and start filing.
   

 I've added this screenshot for your reference when you're already on the File 1099s page:

Furthermore, learn how you can access payroll reports about employee information, wages, taxes, deductions, and other payroll reports for your business. I've added this article so you can check out the lists: Run Payroll Reports.

You can always let me know if you still have any other questions about vendors being tracked with 1099s. The Community is always here to help you all the time. 

Hello there, MgtConsultant.

Allow me to help you out and ensure that vendors are added in 1099's in QuickBooks Online.

Aside from ensuring that their payments met the $600 threshold, were processed by check, and were applied to the correct expense account. We also need to make sure that the contractor/vendor is active and is set up for 1099 tracking.
 

You can check out (Step 1: Make sure your contractor is active and set up for 1099 tracking) article for the detailed steps depending on the product that you have: Troubleshoot missing contractors or wrong amounts on 1099s.

I've also included these articles to assist you in preparing and filing your 1099s. This ensures that you can file them on time:

• Create 1099 reports in QuickBooks
• Create and file 1099s with QuickBooks Online

Keep me posted if you need more help managing your 1099. I'll be happy to help. Have a wonderful day!