Ask HN: How can someone contact Facebook to resolve overcharging for ads?

Facebook recently charged me 7x the budget limit set for a 24 hour ad placement. All previously existing contact forms are gone or broken. Has anyone successfully contacted FB for this type of issue? Any FB devs who can shed some light on options? I'm a small one man op and these charges will destroy my budget for the next month. Right now it looks like a chargeback is my only option.