I was convinced that if pick orders online I will get paid but I should top-up my account when Im done picking orders I will get my money with commission but when I was doing my second last order I was asking to top up again the sum of 27000 on top of 450

I was convinced that if pick orders online I will get paid but I should top-up my account when Im done picking orders I will get my money with commission but when I was doing my second last order I was asking to top up again the sum of 27000 on top of 4500 that was already on their account which I did the top-up and again when I was doing the last they ask again top-up with 78000 which it was difficult for me to do it because I did have that kind of money,I ask them to refund the money I've already paid and they refuse saying if I can't top up Im losing everything I've already work for. May you please assist me get my money back please