The buyer had already sort of broken the contract first by not upholding the payment terms, then he asked us both for nude pictures at 17 (possibly/probably illegal). Now it turns out (two years later) there was a problem on our end of the contract, but has the contract already been voided? Our main argument is that both of us didn't have the capacity to agree to the contract. Obviously I won't take any advice as definitive but it would help massively. Cheers.