I've just got a response from this email.
"Your browser is hacked. Send 0.5 btc to bc1qhrdvuxrealra5xm7qsu9tyh06k3frcrzuvsms7 to unlock it. Why trust me? I cant withdraw your money because it needs otp and email. Ill wait 1hr before I drain it"

Freebitco doesn't have telegram support system, and the email you shared isn’t the official support email address of Freebitco. Therefore, your browser has been indeed hacked by someone. Otherwise, your desktop has been compromised. Haven't you tried to login from another browser or device to your Freebitco account? Which browser you are using now? Try to login to all the accounts on another device instead of sending anything to the hacker.