Unauthorized Withdrawal

I am currently taking care of my Ex wife's AMx debt due to a separation agreement and the account was being handled by Collectcorp. I was authorizing Collectcorp a single month by month withdrawal from my bank account where they contact me every month prior to the due date and get authorization to withdraw the money. My Ex-wife recently violated the separation agreement and I stopped making the payment. I last authorized payment in March of 2011 and then left the country on the 31st of March. So collectcorp had no way of contacting me but withdrew money in April, May and June without my authorization. I returned to the country on June 10th and discovered what was going on around June 30th. Again the account is not in my name nor is my name attached to it in any way I was just paying it as part of a separation agreement which was violated by my Ex-wife. I never gave Collectcorp authorization for multiple withdrawal at any time and all our prior conversations were recorded and all indicate me refusing to authorize a payment plan and my wishes for a monthly authorization and all prior withdrawals were all for a single authorization for around the 20th-22nd of the prior months.
Did Collectcorp violate any laws and can I take legal action against them?