The latest victim, a woman, aged 89, who has restricted mobility, received a call at her home in Netley Close, Cheam, on Tuesday, 1 December shortly after mid-day.
A short while later, a courier arrived for the card and also asked for her PIN and what cash she had available.
She handed over £340 cash and had £240 withdrawn on her card once the courier had left.
The suspect is described as a white male, aged 25-30, 5ft 8in tall, of slim build with short, brushed back, brown hair. He was of smart appearance wearing dark trousers and dark jacket. He was described as 'smiling a lot'.
Police advice is that you should always be suspicious of callers asking to see or collect your bank card and asking you to reveal your PIN because your bank will already have your account details and they would not ask for your cards to be returned to them.
If you are suspicious of anyone calling at your door, shut the door keeping them outside, and call police on 999. We would rather come out and check that everything is OK, than to find someone has become a victim of crime.