The phrase &1 &2 is from a passive library

Message type: E = Error

Message class: /SEHS/PH_CM_DATA - EHS: Phrase Data (Phrase Header, Phrase Item, Phrase Ref.)

Message number: 003

Message text: The phrase &1 &2 is from a passive library



What causes this issue?

The phrase &v1&-&v2& has been taken from a passive library.
You cannot perform the following activities for phrases from the
passive library:
Combine several phrases to one phrase
Assign to a phrase set

Error message extract from SAP system. Copyright SAP SE.