A timely warning, "Slamming"

Don't trust BT to do as you ask.Received the above, called on three seperate occasions, to say it was incorrect and please cancel. Assured by all I spoke to it was sorted and not to worry. Guess what, been without broadband since the 1st and through no fault of my own I'm still without and will be for the foreseeable future. This practice is called Slamming where another provider requests without your knowledge or permission, to take over your line and services.
Thanks to a nice neighbour, I am piggy backing off her Plusnet provider, hence my ability to post this....
As a ps to this, check on Google just put in the word Slamming and you will get several hits.
Don't think it can't happen to you, over 250 thousand people a year have this problem....