QB Issue Resolution:

odd I just tried mine and it works as expected
In Desktop, back up the file then use the main menu File>Utilities>Rebuild and  run it as many times as necessary (but at least 3 times) until it completes, then run verify (if there are still errors run rebuld again), then close QB and re-open it and see if it helped

Resolution for Issue 'How do you change an account that was mapped to a 1099? Even changing it to “omit these payments from 1099” does NOT work. How do I completely delete it from the mapping?' available: Yes (Solved).
Source: Intuit Community forum.

How do you change an account that was mapped to a 1099? Even changing it to “omit these payments from 1099” does NOT work. How do I completely delete it from the mapping?: 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.

Support for completely delete
Quickbooks Repair Pro will resolve it efficiently and affordably. Guaranteed resolution of your issue, or you pay nothing!

Error Recovery for completely delete [Canada]
E-Tech is the #1 Quickbooks data migration and Conversion service provider.

Get 50% off Quickbooks Online

Click Here for 50% off!

Additional Support Options: