Well, Based on the cron you have there, it actually ran at the right time.
You have it set to run at every 2nd and 3rd minute. Six minutes after the hour is divisible by 2 and 3. So it ran.
I’ve been using the cron and it seems to run very well.
If you want to offset the minutes, try using seconds.
* The cron format consists of:
* [SECOND (optional)] [MINUTE] [HOUR] [DAY OF MONTH] [MONTH OF YEAR] [DAY OF WEEK]