A few months later I asked how to reopen the account, using the "reopen account" form in their app to generate a support ticket. Three weeks later they sent an email saying that my account was permanently closed and I should apply for a new account. Replies to this email yielded a response saying that their email server was failing to accepting messages.
So as requested I applied for a new account; the application stayed pending for three weeks, then I got an email autoreply telling me that my application is denied because I have a preexisting account (i.e. the old closed one). Replies to this email also yielded a response saying that their email server was failing to accepting messages.
I filed a new support case explaining what had happened, what they told me to do, and asking what I should do next. No reply whatsoever.