Security Session Audit Report

Hi

I logged onto MYOB this morning at approximately 8:06 am.  However, when I ran the security session audit report, it shows me as having "successful logon to the file" at multiple times between 12:00 midnight and 7:30 am, prior to my actual log on at 8:06 am.  If I re-run the report, it regularly shows early morning logons using my ID at minute intervals for approximately 15 minutes between 4:45 am and 5:00 am.  There are occasional logons for user ID SYSTEM.

Why is it showing me as logging on at times that I am not logged on.  I have two factor authentication activated and no reason to believe that anyone else has my username and password combination.

Thanks.