Client confidentiality

Client confidentiality is a principle that an institution or individual should not reveal information about their clients to a third party without the consent of the client or a clear legal reason.

This is the scenario we found ourselves in today. A person who we have never heard of rings for support claiming to be from a client of ours that he claims has gone bankrupt asking for information on how to get into our clients point of sale software to get its data. He provided no further details of who he is other than what we presume was his name and a phone number. What he claimed was that our client had gone bankrupt and he had brought all the assets. The problem we had is that we had had no notification from this business or anyone claiming to represent this business eg a the liquidator or solicitor by which we usually get informed in such situations.

When we rang the owner of the shop to get authorisation to help him, we could not contact anyone in authority. So what do you do?