Scheduling Job In Stored Procedure

PFB code i used to schedule a job as per my requirement. And the procedure is executing fine, but when im about to run it is getting hang.

create or replace procedure scheduler_alert(frq varchar2,intrvl number) is
begin
dbms_scheduler.create_job(
job_name=>'scheduler_alert',
job_type=>'stored_procedure',
job_action=>'alertlog_error',
start_date=>SYSTIMESTAMP,
repeat_interval=>'FREQ='||frq||';INTERVAL='||intrvl,
enabled=>true,
auto_drop=>false);
end;
/

When im trying to run the job it is getting hang.

exec dbms_scheduler.run_job('scheduler_alert');