ORA-01153: an incompatible media recovery is active

Cause: Attempted to start an incompatible media recovery or open resetlogs
during media recovery or RMAN backup . Media recovery sessions are
incompatible if they attempt to recover the same  file. Incomplete media
recovery or open resetlogs is incompatible with any media recovery. Backup or
restore by RMAN is incompatible with open resetlogs

Action: Complete or cancel the other media recovery session or RMAN backup

SQL> recover managed standby database cancel;

SQL> recover automatic standby database;

SQL> RECOVER MANAGED STANDBY DATABASE DISCONNECT FROM SESSION;

SQL> SELECT MESSAGE FROM V$DATAGUARD_STATUS;