Well, this certainly doesn’t mean that you owe anyone money!
Although highly uncommon, some of the merchants that work with us may not edit the commissions whenever an item is returned. They instead might post negative values on the day the item is returned. This amount will match up to multiple past commissions and will be deducted from your total earnings from the months payment.
Essentially, the lesson here is that you don’t have to worry and you do not owe anything, the system will take care of all of this.