Although written from the perspective of correcting errors on your US credit report, this blog post has plenty of good portable advice on how to complain to banks about pretty much anything. http://www.kalzumeus.com/2017/09/09/identity-theft-credit-reports/ Some key points: only send them paper letters. This is a really weird thing for a technologist to suggest, but when you send paper letters, you can establish and own a “paper trail.” communicate with the bank in a manner which suggests that you’re an organized professional who is capable of escalating the matter if the bank does not handle it Showing anger decreases the perception of risk of you filing a regulatory action or a lawsuit. Angry people demand; professionals “require.” Be very clear about what you want. You want a specific set of actions, you want those actions to be confirmed to you in writing, and you want them done by a specific date. Don’t say untrue things. You can, however, be a professional who says things that have some strategic ambiguity. Say that you will accept further communication about this matter ONLY in writing and all other forms of contact are inconvenient. You can involve a lawyer, but the sums of money involved are generally not cost-effective for most people. I'm posting this here because before going to the FSO you will have to exhaust an institution's internal complaints procedure, and the above tips will help you either resolve it internally or efficiently extract a Final Response Letter.