Hi 혜원 김1,
Welcome to Microsoft Community.
As per the shared information, it seems like when you try to login your accounts, it displays the error AADSTS50020. Usually, that message can happen if you have a personal "Microsoft" account using the same email address as your Microsoft 365 "Work or School" account. If this is your scenario, many people resolved by using an incognito browser so that no credentials carry over, and then choose the related account to log in.
If the error persists, from my search in Abode Cloud Community, it seems like the same error happened on many other users before: Solved: User account from identity provider 'live.com' does not exist in tenant - Adobe Community So, based on the support experience from Adobe engineers, it requires to add your account to the SAML Auth App Tenant to resolve this error.
Hence, please contact your tenant admin and share this Abode thread link, so that IT can know how to add you correctly and grant your account permission to use Adobe Cloud. Here is a reference for how to find tenant admin: How do I find my Microsoft 365 admin? - Microsoft Support
Please accept my apologies and regret that I did not resolve the issue and redirected you to IT admin, but the solution to this error can be achieved by the related setup and please understand that community moderators here are unable to access your account to fix this for you. So I am redirecting it to the right path to solve the problem.
I am sorry and apologize for it.
Your understanding and patience will be greatly appreciated. I hope you stay safe and healthy!
Sincerely,
Mia | Microsoft Community Moderator
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