Controleer schema permissions database user

 SELECT state_desc
    ,permission_name
    ,'ON'
    ,class_desc
    ,SCHEMA_NAME(major_id)
    ,'TO'
    ,USER_NAME(grantee_principal_id)
FROM sys.database_permissions AS PERM
JOIN sys.database_principals AS Prin
    ON PERM.grantee_principal_id  = Prin.principal_id
        AND class_desc = 'SCHEMA'