Cognizant — Unable to login to onecognizant (external) portal post-registration

Hi Team

I've sent 9-12 emails to C2C support for the same issue. But, Still didn't get any response or resolution from anyone. I'm unable to upload documents in the OneCognizant portal after registration. All the details are submitted. Only document upload is pending. For the last 1 month, I'm trying to log in to that portal but every time I'm getting the below errors. I've tried everything - clear cache, cookies from the browser, accessing the portal from private/incognito mode, etc. but none of these are helpful.

Link - https://onecognizantexternal.cognizant.com/?type=1

Error1:
AADSTS90072: User account '[protected]@gmail.com' from identity provider 'live.com' does not exist in tenant 'Cognizant' and cannot access the application 'https://onecognizantexternal.cognizant.com'(ENT_onecognizantexternal_SAML_PROD) 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

Troubleshooting details
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Request Id: 8ab84ef3-be40-43f9-87ab-cfdf218b1600
Correlation Id: cee73712-14a4-4636-ab4e-94653f44d07d
Timestamp:[protected]T15:53:17Z
Message: AADSTS90072: User account '[protected]@gmail.com' from identity provider 'live.com' does not exist in tenant 'Cognizant' and cannot access the application 'https://onecognizantexternal.cognizant.com'(ENT_onecognizantexternal_SAML_PROD) 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

Error2:
AADSTS90072: User account '[protected]@gmail.com' from identity provider 'live.com' does not exist in tenant 'Cognizant' and cannot access the application 'https://onecognizantexternal.cognizant.com'(ENT_onecognizantexternal_SAML_PROD) 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
Troubleshooting details
If you contact your administrator, send this info to them.
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Request Id: 1476935d[protected]e-aac8-4c87f063d900
Correlation Id: 39e7fdfd-ffd2-443b-a119-0541c9e7316b
Timestamp:[protected]T09:11:36Z
Message: AADSTS90072: User account '[protected]@gmail.com' from identity provider 'live.com' does not exist in tenant 'Cognizant' and cannot access the application 'https://onecognizantexternal.cognizant.com'(ENT_onecognizantexternal_SAML_PROD) 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