In case you haven't already tried, I would contact their legal department. I would expect them to be far more invested and effective in fixing these breaches than anybody in the phone-based customer support chain.
> [A bank's] CS department is scored on number of tickets resolved per hour, and each rep’s incentives are simply to classify you as something requiring no followup and get you off the phone. [...] The legal department (or an analogous group – it is different at every bank) is not scored on cases resolved per week. They are scored on regulatory incidents per quarter, and their target for success is likely zero. Shockingly senior people will be involved to avert regulatory incidents.
src: https://www.kalzumeus.com/2017/09/09/identity-theft-credit-r...