Hi Abhishekh,
My bad actually, the Portal role assigned to the user is SUCO role Bidder.
Please find below the display name for the same:
Display Name: com.sap.pct.srm.suco.ro_bidder
Just for your information, we deleted the customized roles assigned to the user in the back end and instead gave the standard roles but still we are facing the same issue.
So, one thing is confirmed that this issue is not because of the customized back end roles which are nothing but copy of the standard roles.
BR,
Anurag