Oh Boy, where do I start?
Pipex Internet is (IMHO) the worst example of an ISP that this country has. I have been asked to intervene for many unhappy and miserable customers of this company. I have had banks telling me that other than AOL, Pipex Internet is one of the worst offenders for unauthorised withdrawals. They have gone from being one of the best ISPs to one of the worst in a matter of months and they are simply getting worse by the day.
In your case, I would send a bill to Pipex Internet's Registered company address (Stoke Mandeville) and demand payment within seven days. Then process this through the courts (as I did).
Pipex does not have Customer Service, they have Sales R-soles and Management R-soles. Neither of them knows one iota about dealing with customers either politely or truthfully with the result that many more enlightened customers realise that they would achieve far more if they simply stuffed wasps down their 'Y' fronts (or bras as the case may be). It is a more pleasurable experience than dealing with the Neanderthal cretins that simply do nothing other than steal money from people and then fein ignorance when they are challenged.
In five years of dealing with this Zenith of Crapdom called Pipex, I have never once had a telephone call returned or a technical support issue resolved. I have been lied to, cheated, sworn at and hung up on no end of times to the point now that if a customer calls our support line and states that they are with Pipex, we now record all conversations with date and time stamps. Of course this does nothing to alleviate the issues as Neanderthal Pipex Cretins (NPCs) cannot read or write, but the satisfaction of hearing the grunts and snorts as they try to fob you off with the Pipex School of Excuses (excuse number 17,475 - "Oh, your PC needs to be reformatted to DOS 3.2 before you can use our software") still raises a smile.
When we finally had enough of Pipex, we cancelled the contract in writing and by e-mail. Pipex continued to take money from the account without authorisation for six months before we issued court proceedings. They ignored the summons, the judgement and the first of the bailiffs calls before they finally woke up to the situation and were forced to pay back what they had stolen.
Want to deal with Pipex? Not if they were the last ISP on this planet!