They informed me they are able to recover my lost funds and this is the email they sent me:
"The scammer's security is very right. IP is highly protected but during the recovery process we can hack their data and disclose to you who they are. Recovery with us takes 4-6 hours. All you have to pay is the registration fee on Blockchain to enable us to cooperate with Blockchain for a successful recovery. Because without the help of Blockchain recovery cannot be possible."
After a scam/theft is before another scam. What those idiots wrote to you, is so much bullshit in so few sentences that my brain already hurts. Seriously, this is just another attempt to scam you because you're desperate to get back what you've been stolen. What do you think why they want a payment upfront. I know the answer and it's not to cover their hard hacking work. Don't fall into another scam trap!
Do you believe what they have to say?
Absolutely not, it's total bullshit.