Hi Sandeep,
Please check the following customizing:
==============
t-code SPRO..->
SAP Supplier Relationship Management
SRM Server
Sourcing
Define Sourcing for Product Categories
Category ID SourceSyst Sourcing
* Sourcing Always Carried Out
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Please note if you set 'Category ID' as ' * ', source system should be blank since no unique assignment is possible.
However some users refused to keep this as blank, instead they set it as one backend system. This will not update source_rel_ind correctly in some special case.
Best regards,
Ivy