Blanket Purchase Order notification is not showing when creating a requisition

Hi I have defined Approved Supplier List, Sourcing rule and assignment for a particular item.

I have also enabled checkbox 'Notify if blanked PO exist' in purchasing Options

at user profile level i have also assigned above sourcing rule to 'MRP:Default Sourcing Assignment Set' and set Profile option 'PO: Override Approved Supplier List Status' to No.

but still when creating requisition,Created Blanket PO notification doesn't appear.

Before raising request i have extensively search everywhere for the solution but still problem is not solved.

I am using EBS R 12.2.6 in virtualbox

Any help will be greatly appreciated

Regards

Satyendra