Unauthorised account transactions

I have tried to file a complaint against these charges of $19.99 and 5 charges of $29.95 but they have informed me I need to contact SEM. As I didn't sign up to or received anything from this company I am at a loss as to how I get my money back. I do not even live in the USA so I don't have an address to use for authorising a refund to my home address. Can anyone help me? I can't afford to throw away ~$290