This doesn't affect a single individual - it's another generic failure, including another failure of the Plusnet billing system. Rather than leave people to plough through the whole Community topic Simon linked I'll summarise the situation:
What has happened was that some months ago Plusnet made changes to the home phone packages. Customers were sent notification which included a link to a blog posting on the Community site describing the changed products which included the following:
The sharp-eyed amongst you will have noticed there is a slight increase in the line rental element of the products, this is prompted largely by an increase at a supplier level, and is the first price increase we have had in over 2 years.
...
If you�d like to see the new tariff details in full then please have a look here.
Note that the only price increase referred to in the blog post was in the price of the line rental.
Buried within the PDF linked at the end of the post was a massive increase in the price of the Anonymous Call call feature. The OP had not noticed this - it's pretty obvious that this is not adequate notice!
To compound this the billing system wasn't updated and for some months it continued billing at the old price; it has now been updated and Plusnet are trying to claim back payment. I guess many of the people who had opted in to the Anonymous Call feature may have second thoughts about it's usefulness when the price has gone up so much, so hitting them with a demand for back payment when they may have cancelled the feature after the first month when they realised the extra cost (or even immediately they received notification if Plusnet had given proper notification).
I've had a number of run ins with Simon in the past, but in this case having spotted the issue on the Plusnet forums I think he was fully justified in flagging it up here so that any other users affected can see they are not the only ones who are very unhappy with the situation.
My own opinion is that they would be fully justified in refusing to pay the back fees if they are not intending to continue to use Anonymous Call because of the massive price hike (IANAL).
jelv
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