I am getting the following error when trying to login to the challenge portal.
Request Id: ede11060-14eb-48fa-ad08-2a4bee2f0100
Correlation Id: 84cbef46-b4df-4f0e-acb7-42af3229e628
Timestamp: 2021-06-15T20:07:19Z
Message: AADSTS50020: User account 'mvsastry@optimum.net' from identity provider 'https://sts.windows.net/d5766cc8-5dd8-465c-8e26-8301b9cace39/' does not exist in tenant 'Microsoft' and cannot access the application '7b7fd2e0-3170-4675-9f8b-9948a4febd0d'(CloudSkillsChallenge (CSC) PROD site) 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.