Hi @Ben Shabat, Zahi , 53003 indicates that your account is not eligible for Conditional Access. This can occur if the user account is not licensed for Entra ID Premium or Enterprise Mobility + Security (EMS) licenses. Since you have an Entrust Basic subscription, you may not have access to the Conditional Access feature.
If you are an external user, you may need to contact your admin to check if your account has the required licenses and permissions to use Conditional Access. If you are the admin and still can't login, please let me know.
Please let me know if you have any questions and I can help you further.
If this answer helps you please mark "Accept Answer" so other users can reference it.
Thank you,
James