[Solved] Event scheduler automatically getting logoff

I have created the event that update the status after 5 days and i used this event query...

CREATE EVENT rot ON SCHEDULE EVERY 1 day DO 
    update barter_proposals 
       set proposal_status="Aborted"
     WHERE sent_date=DATE(CURDATE()-5)
       AND proposal_status = "Sent/Received"

So Based on current date,the sent_date got updated.(i executed the event on 28th april(System date))(23rd april status got updated)

i checked on next day ie. on 29th april.i found that 24th april status dint got updated and i also found it shows event schedular as OFF.

CAn anyone tell me why this happened?