Hi Vishal...
I'm not sure I completely understand your scenario. Are you saying you'd expect a User to be able to login to ISIM even when the User doesn't have an ISIM Account (and/or the ISIM Account should be created automatically)?
Typically our customers that use both ISAM and ISIM (with ISAM providing SSO to ISIM), have ISIM configured to provision both ISIM and ISAM Accounts when Users are onboarded. After that point, the Users can authenticated to ISAM and access ISIM when/if needed.
Since it appears your users are federated via some external application, you could create an ISIM datafeed that pulls data from that external federation, which would create the Users/Accounts in ISIM.
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Grey Thrasher
IBM
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