Unable to withdraw

I saw the advert on Facebook saying that I was going to get 1.5% of my investment when I start trading with the company, then I had to invest $250, after investing the they later told me that the prices have been upgraded, so for the first package which is $250 is now $500 so i have to pay another $250 making it $500 before I can be qualified. Then after that they stopped replying my message that was when I knew I was scammed.