ORA-16139: media recovery required SWITCHOVER_STATUS SWITCHOVER LATENT

SQL> select switchover_status from v$database;

SWITCHOVER_STATUS
--------------------
SWITCHOVER LATENT

SQL> alter database commit to switchover to primary with session shutdown;
alter database commit to switchover to primary with session shutdown
*
ERROR at line 1:
ORA-16139: media recovery required


SQL> RECOVER MANAGED STANDBY DATABASE FINISH;
Media recovery complete.
SQL> ALTER DATABASE COMMIT TO SWITCHOVER TO PRIMARY;

Database altered.

SQL> select switchover_status from v$database;

SWITCHOVER_STATUS
--------------------
NOT ALLOWED

SQL> select db_unique_name,database_role,switchover_status from v$database;

DB_UNIQUE_NAME                 DATABASE_ROLE    SWITCHOVER_STATUS
------------------------------ ---------------- --------------------
MEDDB                          PRIMARY          NOT ALLOWED


SQL> alter database open;