Despicable - & operating illegally & immorally.

I am representing a friend who has mental health problems and who has been stitched up by Optimum's door-stepping salesmen. She is depressed and at her wits end.
She was sold the contract (despite telling them she was ill and depressed and trying to cancel a phone line with BT). They said - No problem, we'll cancel your other line (business) and it will be cheaper for you".She didn't want to proceed but could see now way of ridding herself of them.
They didn't cancel the line - she has continued to be billed for it.
She has tried to move to PlusNet - Optimum have said she can't have her own number, there's a £395 cancellation charge (unless she stays until 29th March 2015) and to get her OWN PHONE NO. BACK IT'S £49 plus VAT IF SHE STAYS WITH OPTIMUM. No guarantee she will get her own number (owned for 20 years with BT) back. She has been earning £400 a month!!!! I don't intend to let this rest and she has asked me to represent her. I am horrified to find all these reviews !