More than likely they didn't know about it beforehand, their address is listed, try sending them a polite registered letter, clearly documenting, the sale, your problem, their lack of response to your emails, and ask them to rectify the matter.
You might be very surprised at the results, just don't let your sore attitude affect your attempt, complaining won't get you very far, but a polite registered/receipt requested letter usually opens eyes! [
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