today I was called into the office where I work, the company I work for issues and collects loans from peoples homes, I had done a loan for a existing customer who has done a runner, I had been pulled up in the office as the signeture from the first agreement is abit different from the new agreement, we cannot get incontact with this customer as the manager thinks I have signed the agreement myself and kept the money. how do I go about proving my inoccence?