An "engineer" from 5G Communications arrived uninvited at our offices with a questionnaire and diagrams and spoke technically about recent upgrades of BT lines to optic fibre. He gave the impression he was acting as an agent of BT and was here on technical issues. His questions covered our outside lines, internal telephone system, broadband, mobile phones and who managed our calls and lines and became ever more intrusive and unlikely to have any connection to BT but he could not answer my basic question of "why exactly are you here?" He kept repeating stock phrases which had no meaning. He was reluctant to go until I spoke to his "boss" on his mobile. He said he had to complete his survey before he left as if it was my problem. The boss said that a named person in our company had requested a visit which was not true.