FixedFloat was hacked.
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Thank you for the transparency regarding this communication. I saw that you omitted the name of the person that got in contact with you but you left his name on the e-mail. Perhaps it would be better to hide it as well.
I wasn't aware of this hack but I can see that it is very recent[1] and already $26M have been drained:
Since Feb. 17, a number of users have reported frozen transactions and missing funds on the exchange’s X page. On-chain data shows that more than 400 Bitcoin worth around $21 million and over 1,700 Ether worth nearly $5 million were drained on Feb. 18.
[1]
https://cointelegraph.com/news/fixed-float-confirms-26m-exploit-bitcoin-ether