SAP Message WPLG009 - Call module is not maintained; see long text

Diagnosis
A function module, in which the interface parameter is transferred andthe external program is started, is necessary to call the externaloptimization program.
The interface of the function module must be a copy of
'SHELF_SPACE_MAP_OPT_ASCII_GEN'.

Procedure
Maintain the name of the call module under SpaceManagement Interface
in the IMG activity General Control, Retail MasterData