They say it's plausible, but I can't withdraw my money.

I signed up for a stock tip ad on sns, got a call from a rep asking me to deposit in ethereum from bitflyer, deposited, private platform shows my investment and bonus, after 2 weeks of operation it tripled and they want me to increase it further, I tell them I want to withdraw the money and reinvest it, they say "when you withdraw it, you have to prove that there is no fictitious account or money laundering through the blockchain, so we have 30% of your money with bitflyer. I tell them that I want to withdraw once and reinvest, and they tell me that I need to show 30% of my funds to BitFlyer (which I only need to do) to prove that there are no fictitious accounts or money laundering through the blockchain. Then, I get a phone call claiming to be from the blockchain, asking me to prepare additional funds since the original pending amount is not enough since my profit increased during the few days before the procedure. The conversation ends with them saying, "We can't provide you with any more, so please offset the amount from your profits." They both speak Japanese with Indian accents on the phone from England.