[otrs] (no subject)

I keep getting these errors in our system log OTRS-GenericAgent-10 Can't create PID GenericAgent, because it's already running (domain.com/15148)! The domain was changed in the email and the number is different on each line of the log. I was also wondering how to clear the system log. I have fixed most of them and need a clean log to see if they are coming up again. Thank you Dillon