How is this legal?

Long story short, around 2016-2017, I was heavily into crypto and used to trade pretty regularly. I think I had about 3 different accounts with Coinbase at the time (not sure of the rules back then). However, I quit crypto altogether during that time, and shortly after, Coinbase banned me for unknown reasons. I did not pursue it further since I had quit crypto, and something like 0.1 BTC was worth less than $100, so I couldn't care less.

Recently, I have been trying to get back into crypto, and yesterday, I tried to open a Coinbase account (completely forgetting that I was banned almost 8 years ago) when it instantly got banned again. Coinbase never really gave me a specific reason why I was banned, and even today, when I reached out to their support via X, they still wouldn't tell me why I was banned.

Anyway, it's all good. It's their website, and they are free to ban me and not allow me to use their service. Thankfully, I can go to something like Kraken/, etc. However, the issue is that the 3 accounts they permabanned back in 2016/2017 likely had an outstanding amount. I told support today if it was possible to get that outstanding amount withdrawn, and they said they can't do anything. They couldn't even check if any of my 3 accounts had any outstanding balance (refer to the screenshots below).

My question is, is this actually legal? I understand a website has the right to deny you service, same as a bank or a crypto exchange, but if you have an account with that exchange, shouldn't they at least allow you to withdraw the amount before permanently closing your account? Really, I don't think those 3 accounts had much, but back in 2016/2017, 0.1 BTC was like $100, so I probably didn't care. However, even 0.x or 0.0x BTC is still a good amount. I was hoping to log in and see my balance, but all my accounts are banned. What do you guys recommend?

Here are some screenshots of what I received from their support and also the email of my account closure, which provided no reasons for why I was banned: