Payroll screw ups

Ok, don't know if I mentioned this before or not. Like my second paycheck as a Perot employee had a big screw up. I had been shown how to enter my time into the system all wrong and had over 40 hours overtime. My check was HUGE! Bigger than Mark's ok! Anyway, I talked to payroll and we corrected all my time. The lady then told me the next paycheck should be like $600 short to correct things. She thought it would do it automatically since we corrected my time. So, this meant I had to budget the fat check I had just gotten to make up for the small one coming. Well, the next check rolls around and it's normal. No $600 missing. So, I called payroll and got the same lady. She said ok, she guessed it didn't automatically take it and she would have to do it manually on my next check. Budget time again. Well, guess what, I just pulled up my banking info. online to see how much my check that's hitting Monday will be and they didn't take the money again. W T F? Don't they want or need it back? Guess I'll get to call payroll again tomorrow and do the whole budget thing all over again. Maybe they can get this right before the end of the year. Or say fuck it and let me keep it for all my trouble. Right.