Scheduled Job Does not work in oracle SQL*PLUS
Try this:

BEGIN
    DBMS_SCHEDULER.CREATE_JOB(
        job_name        =&gt; 'delete_old_rows',
        job_type        =&gt; 'PLSQL_BLOCK',
        job_action      =&gt; 'delete_trips;',
        start_date      =&gt; SYSTIMESTAMP,
        repeat_interval =&gt; 'FREQ=SECONDLY',
        end_date        =&gt; add_months(sysdate,12),
        auto_drop       =&gt; FALSE,
        enabled         =&gt; TRUE
    );
END;
/


You don't need the EXECUTE part in job_action.

You can check DBA_SCHEDULER_JOBS.NEXT_RUN_DATE to check when it's next due to be executed. Obviously you can also check the other relevant columns to see if it's actually executed and/or failed (LAST_START_DATE,FAILURE_COUNT etc). Table doc link.