Is it okay if I got my employer to pay me 6.5 hrs of extra pay by mistake?
Do you feel the extra hours are worth it?
Yes, I can use the extra money.
Regardless of whether you need extra money, it is wrong to lie to your employer about the time you worked. If you need extra pay you should work more hours.
What if the extra pay is more than what I could make by working more hours?
Then unfortunately it is money that you did not earn. Your employer can very easily see the records of your actual hours and reprimand you. It is best to report this kind of mistake, your boss would take notice of your honesty and maybe consider you in future promotions.