I've had nuisance calls from what was my telephone provider having given my unlisted number out. I had indicated directly to them that I was not to get marketing calls, I was on the do not call register and as it was ex-directory, they couldn't have just got it from the phonebook. They tried to get around these directives by saying that it was not marketing (no, they just wanted me to buy a new mobile phone, that's not marketing, is it?) and that the sales agency was actually just them (it's not).
Rules are meaningless to the crooks, and also to some (many?) legitimate businesses too. We have an agency that is meant to deal with this, but they won't. You need to just handle it by yourself.
