Phoning on my private number to sell funeral cover despite trying to opt out

Periodically I get machine automated calls selling funeral cover. I have tried just putting the phone down, but this means I just get more calls. I have tried listening to the whole message and then opting out but to no avail. Today I tried pressing 1 so that I could actually tell someone to take me off the system and I was told someone would get back to me. I got a call from Margaret whom I asked to take me off their contacts. She then said she couldn't. I said if she didn't I would refer the call to the ombudsman. Again she said she couldn't and she said I must phone head office. I then got annoyed and asked her who she worked for and she said Clientele so I said then she must be able to organise to have me taken off and again she said I must phone head office. Annoyed, I rep**** that why should I waste my money on a phone call when this should be sorted out by Clientele. With that (while I was still talking) Margaret said good-bye and have a nice afternoon madam and put the phone down on me.