Thank you for your super fast response. Yes she was on the banking mandate, we had originally started the company together but this all happened after she was no longer a director or shareholder but still had access to the banking as she helped me with the financial organisation etc. I agreed to lend her £3000 for her new start up and then the next thing I knew the company account had been emptied and the credit card maxed out.
No the mandate was set up to need only 1 signature. It was paid out in a mixture of ways, some she paid to herself personally, some she paid for goods and services for the new company using her card.