NO Leads FOR MONEY

Hi this people require me to pay for leads during December month to get some leads from them for January 2018. When I keep on following, they apply back that they do not have the business any more and that they will pay my funds back. Afterwards they came back and said they cannot pay it as they do not have funds. So how can you get funds from your clients if you know you do have a problem? I keep on contacting them ,they do not come back at all and if they answer, they said they will come back, but they never came back so far. I really think this was just to make funds over the festive time that is why they do not response now.