Be/do something for your sins
Definition 1 of 1
Pro Tip 1/3Colloquial Usage
The phrase is casual and might be unclear in formal or non-UK English contexts. 
He's doing the extra work for his sins of missing the deadline.
Pro Tip 2/3Not Literal
It's often used jokingly and doesn't usually imply serious wrongdoing. 
I'm on dishwashing duty for my sins of cooking a bad meal.
Pro Tip 3/3Figurative Punishment
The 'sins' are often minor mistakes, not actual severe offenses. 
I'm proofreading the whole report for my sins of typos.