Conflict with Online Jobsite

Hi, I'm a freelancer and have some open contracts with US and Canada clients through jobsite 'Upwork'. Upwork is an online job portal where we can register as a freelancer and bid for the jobs posted by clients from different countries. One week back, upwork asked me to provide the scan copy of any identity card issued by Government of India as well as bank statement for address proof. I provided my Passport details, PAN card details and the bank statement downloaded from nationalized bank several times and each time they rejected the documents without mentioning the reason. They are telling , they cannot reveal the reason for rejection as per their company policy. Now they have permanently closed my account and holds my $150 dollar with them. They clearly states that they are not going to reinstate my account and also not going to pay my money back. Please advice if we can legally do anything in this case. From their website I could understand that they don't have any office located in India. Thanks Laiju CS