Can't cancel

I recently lost my job, so I went to cancel my gym membership (which was sold to me as a month to month contract with no cancellation fees) thinking ending it at the beginning of the month well within the given cancellation time would be best for all parties. Only to be told I will have to pay almost 500 to cancel the debit order. Which is money I do not have. So now I'm forced to leave the debit order of 250 to bounce off of my empty bank account at the end of the month. The guy said the month to month contract was only valid for a 3 month probation period and then I got bumped up to a 12 month contract (WITHOUT MY CONSENT) as far as I'm concerned this was an illigal sale as the contract was not explained to me and I have been blind sighted with a 12 month contract I did not consent to and will most likely have to pay to cancel after the 12 month period or pay to renew for a further time period. This is not the first time virgin active has messed me around and I wish I had the funds to take this further.