QB Issue Resolution:

You cannot change the name type for vendors, employees, or customers.  You can change an other name to be any of the other three types.

To recover from setting up the name wrong, set up a new name that is close in spelling, then edit all of the data using the old name (if desired) to use the new name.  Then you can delete the old name.

You can run the 941x form from the same location you run the 941 form.  If you don’t see it in the list of forms use the button under the forms list to add it.

Resolution for Issue 'How do I switch a vendor to an employee and how do I submit corrected 941 tax forms?' available: Yes (Solved).
Source: Intuit Community forum.

How do I switch a vendor to an employee and how do I submit corrected 941 tax forms?: this issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.

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