This function can only be used for phrases in the active library

What causes this issue?

This function you called is only permitted for phrases of the active
library.

System Response

The function is canceled for all selected phrases contained in a passive
library. However, the system carries out the function if you have also
selected phrases of the active library.

How to fix this error?

Only use phrases of the active phrase library.

Error message extract from SAP system. Copyright SAP SE.