They can and DO do this all the time and its entirely legal and within their rights, and they don't legally have to tell you why. The reinstatement success ratio is not in your favor. Take the L and move on instead of stewing on it because you'll get absolutely nowhere legally despite how you feel.
I had Chase drop me about 12 years ago and I've lived my life perfectly fine without them. It's a good lesson not to put all of your eggs in one basket either.
I'm imagining OP as this:
They have NO RIGHT!!!!!!!!!111
Anyway, obviously they do have a "right" that's laid out in contract and law. That is to say, no laws prohibit a bank from closing all your accounts for any reason or no reason at all (as long as they're not discriminating against any protected classes). If you disagree with this, probably best to write a strongly worded letter to your state and federal representatives.
In the meantime, Chase is known for silly shenanigans such as this, which is why I never bank with them any more. I advise OP to find a better bank (or, better yet, multiple banks and diversify assets). I will never bank with just one bank ever again.
Also, file a CFPB complaint. I've been locked out of banks and always file a complaint. Nothing really happens but at least its in the record.
9 times out of 10, something tripped a BSA/AML flag, and the bank decided to end the relationship as to not take on risk.
A bank doesn't end a relationship entirely over a negative Chex or EWS report. They'd just close your checking account.
