How to stop annoying unwanted call

[somebody]

I'll have a look at that later, that might help me.

I've registered my number with BT to stop unwanted calls and since that I never received any of it at all apart from that one company who kept looking for bloody Mrs Portman!

Try and find out who they are on the next call and then we can see if we can help.

Sometimes writing in helps far more than telling a call operator who cant do anything on their system.