I was contacted over LinkedIn by a broker named Olivia Thomas - Mobile Number +1 (213) 465-3423 with a proposal to invest bitcoin in trading. Accordingly, I've purchased bitcoin and was advised to register and create an account on https://www.octextradings.com.I've sent the requested bitcoins to them (some via the broker and some directly to the wallet addresses provided) and when I wanted to withdraw, they came back stating I've to pay USD 12500 as FINANCIAL TRANSACTION TAX (FTT) which I paid. Then they said the bank transfer was arranged for USD74000. In 2 days they advised that the transfer is being held by IMF and I'm to pay another USD10000 to get the funds released. I did not pay this and in 3 days they said the amount was reversed by IMF to them. Thereafter several attempts were made to withdraw the funds via bitcoin for which they charged me different amounts at different time claiming conversion fee, renewal of signal fee...etc. Finally they sent me a video as proof for transferring bitcoin worth USD174,000 but i received only bitcoin worth USD1. When inquire they said the balance is withheld by the network and I've to another USD7000 as encryption fee to get the same released.