Diagnosis
This error can occur for the following reasons:

• The phrase is not assigned to the phrase set with which the
characteristic can be assigned values. Therefore, you cannot use thephrase to assign values to substances manually.

• One of the value assignments maintained has a phrase without a phrase
set assignment assigned to it. However, you can only maintain thisvalue assignment manually if the phrase without a phrase set assignmentis no longer assigned to it.

Procedure
Assign a phrase with a phrase set assignment as the value assignment.