The man was surprised because Bepin Babu was not recognizing him. Even when Bepin Babu confirmed that he was ‘Bepin Chaudhury’ then also he refused to recognize the man. This can happen to anybody. Usually people don’t talk to a person until and unless they are doubly sure about the person’s identity. Moreover, the way that man is giving detail of Bepin Babu’s Hudroo and Netrahat trips, it is very likely that he did what he was saying for somebody called Bepin Babu.
The man was very much surprised as Bepin Babu didn't recognise the man who told that he had arranged a cab for Bepin babu at Ranchi. The name of the man was Parimal Ghose. But in reality they had never met each other.