Cognizant — Not able to login in 1c portal

I'm not able to login in my 1c portal and carryout the prejoining formalities. My virtual onboarding was on 13th Feb. Due to some medical reasons I could not respond to that. But I got the mail from HR to login in 1c portal and complete the pre joining formalities but I'm getting this issue while login

AADSTS90072: User account '[protected]@gmail.com' from identity provider 'live.com' does not exist in tenant 'Cognizant' and cannot access the application 'https://onecsit.cognizant.com'(ENT_onecsit_SAML_SIT) in that tenant. The account needs to be added as an external user in the tenant first. Sign out and sign in again with a different Azure Active Directory user account