Not the banking industry but I had an issue with a leaked Twilio key once and it was a funny conversation like that. They kept telling me that I had been a victim of fraud (long story, a contractor pushed a key to a public GitHub repo). It only took about 7 repetitions for them to finally acknowledge that it was in fact Twilio who had been the victim of fraud: someone, pretending to be me, had asked them to send $1000 worth of Netflix spam and they obliged.

It wasn’t ever really resolved in a satisfactory way but it got to the point where I was so frustrated and tired that I said “fine, we can settle on $200” because it wasn’t really worth pursuing further (based on my hourly rate and how much wasted time I’d already sunk into it)