Agree with talk talk being the worst.
My Mrs had 18 months of hell , terrible coverage and customer service.
She paid off the last 3 months to allow her to move house, and was billed £250 for her 'Free ' you view smart box.
When she explained she'd paid her full contract up, they explained that in the small print, that if you didn't have the whole 18 months you had to pay for the box, which is bizarre seeing as she'd paid up the whole contract.
Flash forward to 3 attempts by them to send out a jiffy bag for her to send it back, when they failed to show, they sent debt letters and court threats because we hadn't sent it back.
When she did finally receive a jiffy bag, and sent it back, a month later they said she hadn't and were going ahead with the debt collectors.
She kept the post office receipt so she was in the right, and after explanation, they wanted the original receipt for their files.
My Mrs refused and offered a photo copy, seeing as they'd lost a box they could easily lose a bloody receipt.
They carried on with debt collectors letters and cold calling her until she finally spoke to someone with a brain at talk talk