I recently got an SBA loan. After I got the loan the bank was bought or rebranded or who knows what and they moved my account to a new website. I was still able

I recently got an SBA loan. After I got the loan the bank was bought or rebranded or who knows what and they moved my account to a new website. I was still able to log into the old website and, until I tried to update my email on the account, which can only be done over the phone, I didn't notice that they had actually cloned the database, and locked their customer service representatives out of the old one. I can still log into the old system, and update my password from there, thankfully. But I've been unable to change the email address on it because the customer service representatives insist that the old system "has been deleted" and refused to connect me with any engineers or escalate the issue to someone with the ability to solve it. Ironically the old system is still responsible for email notifications, so those are locked to my old email address. I'm pretty sure this is a data leak waiting to happen, but what can I do about it?