AADSTS50105: user isn't assigned to this application
Likely causes
- The enterprise app has Assignment required set to Yes and the user was never added.
- The user was removed from the group that grants access.
- Group-based assignment is used but the tenant lacks Entra ID P1 or P2.
How to fix it
- Ask whether the user should have access. If yes, raise it with the app owner or your identity admin.
- Admins: in the Entra admin center, open Enterprise applications, select the app, then Properties, and check Assignment required?.
- If assignment should stay required, go to Users and groups > Add user/group and assign the user or a group they belong to.
- Test with the affected user. Global Administrators can sign in without an assignment, so testing with an admin account proves nothing.
Checked against: learn.microsoft.com, learn.microsoft.com