Message SAP /ISDFPS/FDPDAMPO214 - Cannot assign line to relocation/relocation step

Diagnosis
The line selected cannot be assigned to the relocation/relocation stepselected. Possible causes for this:
The line selected is not a purchase requisition line.
The delivery date is after the CRD of the relocation/relocation stepselected.
A relocation/relocation step has already been assigned.
The purchase requisition does not refer to a technical object or pieceof master equipment.

System Response
None

Procedure
Select a suitable line.