Read the online company's terms of service. That's your contract, and that governs the parties respective rights and remedies. It should spell out how disputes are resolved, how are where you can take action, whether you have to mediate or arbitrate or give them notice and chance to sure before suing, etc. etc.
It could be that hiring a lawyer to contact them will get a response and/or a refund. It could be this is an Asian company that you'll never hear from again.
Avvo doesn't pay us for these responses, and I'm not your lawyer just because I answer this question or respond to any follow-up comments. If you want to hire me, please contact me. Otherwise, please don't expect a further response. We need an actual written agreement to form an attorney-client relationship. I'm only licensed in CA and you shouldn't rely on this answer, since each state has different laws, each situation is fact specific, and it's impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue.
If you paid by credit card, you may be able to recover your payment if you contest the amount owed with the card company. Review your contract terms with the card company.
DISCLAIMER: The forgoing comment is for general educational purposes only, and is not legal advice upon which the reader may rely as the commenter has no actual knowledge of the facts of the case, has not interviewed persons or examined evidence, and has not researched the applicable law. The comment is based only on the facts provided, which are extremely limited, and may or may not be true. Complete defenses may prevent the success of any claim. Competent legal advice should always be obtained before taking any legal action or filing suit. Readers employ any information provided herein at their own risk.