Sales area & & & does not exist

What causes this issue?

The error analysis of the defective record found that a sales area does
not exist.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

If you no longer need the assignment, please delete the line.
Otherwise, create a sales area and start the assignment again.

Error message extract from SAP system. Copyright SAP SE.