#market-maker-fee

My 'broker' told me my account profits are 'unrealized' until I pay a 'market-maker fee'. Scam?

Long story short, I got into crypto trading after seeing some ads on Instagram. Found a broker, not gonna name names yet, but they seemed legit at first. Deposited a few thousand pounds, and honestly, the trading platform looked okay. I even made some decent 'profits' – or so I thought. When I tried to withdraw a chunk of it, like maybe 8k GPB, suddenly my account manager, who was super responsive before, went radio silent for a bit. Then I got an email saying my 'profits are currently unrealized' and to make them 'realized' and therefore withdrawable, I needed to pay a 'market-maker fee'. They want another 1,500 GBP on top of what I've already put in. I'm based in London. This sounds incredibly fishy, especially after reading about all the other fees people get hit with. Has anyone else encountered this specific 'market-maker fee' after trying to withdraw profits? What even *is* a market-maker fee? Are my funds gone, or is there anything I can do here? I've already reported it to FCA online just in case.