Did you ever get your money back?
I'm still pissed that I have $400 locked up in Robinhood from when I signed up for it and then decided to go with Stash instead. I still haven't fixed that issue, and they don't have a customer support phone number of any kind to call and cancel anything.
Edit: Eh, I ended up just caving in and buying some stocks on Robinhood rather than going through the trouble of checking it for the next week waiting for it to give me the option to withdraw my $400. Did $300 on Tesla and $100 on WWE, two things I kinda wanted but not enough to get during my first spree of stocks yesterday. Now I'm spread across three different investing platforms (Coinbase, Stash, Robinhood) but as I understand it that isn't too uncommon.