I email our CFO in January about an overcharge I noticed on an invoice, something we've been paying $120 a month for, not using, and never used the service. I suggested we contact the vendor and request the charge be removed and try for a credit.

Fast forward 2 months, vendor emails me to let me know that the service is being cancelled and they wanted to give me a heads up that I'll need to find another provider. I decide to go ahead and email back telling them that we haven't ever used the service and we shouldn't be paying for it. After 30 minutes on the phone I got the charge removed and got our account credited for the last 12 months.

Now to figure out how to word it to the boss without making it seem like I'm trying to throw the CFO under the bus for not doing his job.