Cognizant — Unable to register for oneCognizant portal

I got mail from cognizant regrading to complete per joining formalities. But I am unable to login into 1C portal. please resolve problem as soon as possible thank you.

AADSTS50105: The signed in user 'neelimavutukuri57_gmail.com#EXT#@CognizantOnline.onmicrosoft.com' is not assigned to a role for the application 'bb557c9c-73c3-4026-9da2-0b57ec4204b4'(ENT_onecognizantexternal_SAML_PROD).

Request Id: b8106a6c-d7d6-419b-a1de-1bc727ba0800
Correlation Id: e39d7727-4b58-4ea5-af91-e6bf803d17e1
Timestamp:[protected]T15:07:06Z
Message: AADSTS50105: The signed in user 'neelimavutukuri57_gmail.com#EXT#@CognizantOnline.onmicrosoft.com' is not assigned to a role for the application 'bb557c9c-73c3-4026-9da2-0b57ec4204b4'(ENT_onecognizantexternal_SAML_PROD).