A couple of years ago someone associated my email with their bank account in Santander UK. I tried to get in touch with Santander but turned out that the only way to do so is to either make an international call (I don't live in UK) or send them a paper letter. I gave up and just routed these emails to separate folder.

I meticulously report every single of emails like this as spam. Every single one. If it _could_ be read as a phishing attempt, I report them as phishing.

Etc.