Hi @Anonymous User
If your Broadband Bill has jumped from £20 per month to £35 per month, then it looks like the 12 month introductory offer for a newcustomer is finished and you are out of the fixed contract period.
To either cancel your NowTV Broadband & Telephone service or see if they can offer you a reduced price retention deal for a further 12 months, then you need to phone the NowTV Broadband Team.
You will find their telephone number under My Account > Orders & Appointments whilst signed in on here and if you click on the drop down arrow below live date you should then see a contact phone number to call.