Plutonium

It's likely that they didn't explicitly block us, but rather another site that happened to be assigned the same IP as us by Cloudflare (which we use to protect ourselves against DDoS attacks, among other things). Unfortunately there's nothing we can do on our end with our limited budget to immediately fix this, but you (and others having the same issue) can try to complain to them like Xerxes suggested in hopes that they will lift (or fix) the block if they can.