Cold Calls

Has anyone else been subject too cold calls from people claiming to be from Benefits and arranging for you to go to a Medical , even when you are not due a new one, they never ask the usual questions ie security ones or even NI number ?

They claimed to be from Athos/the replacement company , it is happening to my friend , it is always a with held number and they are trying to send him to Marylebone london for a Medical , it has not been long since his last medical . he told the caller he is not accepting phone calls and everything needs to be arranged by post. he is going to try and get his mobile provider to find the number they are calling from. as he had read online somewhere Athos or the New one are cold calling claimants , when not due for medicals , as apparently they are getting bonuses to get people too attend Medicals. They have been harassing him for over 2 months now, and still nothing in writing. Just wondered if anyone else had experienced this at all ?