Hi Gouravraj,
Normally, ISC won’t allow a source to be deleted while it’s still referenced by an Identity Profile. The expected sequence is: reset the source → delete the Identity Profile → then delete the source. The UI enforces this.
That said, there are cases where objects appear deleted in the UI but still exist in the backend, which can lead to this kind of data integrity issue. This seems similar to what you’re running into.
I came across a few threads with the same error, where the workaround was to delete the Identity Profile directly using its ID. The suggested (and marked as a solution) approach was:
***“Fetch the Identity Profile ID causing the issue. If Beta or v3 APIs don’t return it, try cc APIs (if still available). Then use that ID to delete the Identity Profile via the v3 API.”
Plz check this below thread 
Reference: Error While entering identity profiles page
If the API approach doesn’t work, this would likely need SailPoint Support to clean it up from the backend.