Hi,
I want to schedule RMAN backup. So, i created the following job

begin
dbms_scheduler.create_job(
job_name => 'rman07_2',
job_type => 'EXECUTABLE',
job_action => 'C:\Windows\System32\cmd.exe',
number_of_arguments => 2,
auto_drop => TRUE
);
dbms_scheduler.set_job_argument_value('rman07_2',1,'/c');
dbms_scheduler.set_job_argument_value('rman07_2',2,'C:\Users\***\Desktop\rm.cmd');
dbms_scheduler.enable('rman07_2');
end;
/

thanks to many sources from online.

Though pl/sql is compiled successfully, trace is showing following error

ORA-27369: job of type EXECUTABLE failed with exit code: Incorrect function.

Either, there is something wrong with scheduler or my rm.cmd is causing some problem. Therefore, i am posting contends in rm.cmd.
D:\oracle\product\12.2.0\dbhome_1\bin\rman target sys/******* cmdfile=C:\Users\*******\Desktop\backup.txt

Contents of backup.txt is as follows

run 
{
shutdown immediate;
startup MOUNT;  
BACKUP DATABASE;  
STARTUP;
}

My rm.cmd can be run successfully.
Could you please help with this problem that i am facing currently?

declare
  l_rman   varchar2(32767);
begin
  l_rman := 'connect target /
run { 
  backup database;
}';

  dbms_scheduler.create_job(
    job_name        => 'my_job',
    job_type        => 'backup_script',
    job_action      => l_rman,
    credential_name => 'my_credentials',
    enabled         => true
  );
end;
/