Finally United Utilities have responded. I had to search around their web-site to find an e-mail address for their technical department.
Their Customer Adviser said “We had recently experienced a problem with the online payment system but this has now been resolved.”
They should be monitoring payment activity from the site so that they can respond immediately if they see a problem. They certainly shouldn’t wait until someone complains before making a move to rectify the situation. I don’t know if this happened in this case but it looks that way. It is a great way to annoy your customers: get them to enter their 18 digit account number, address and payment details and then have nothing happen when they click the Pay Bill button.
Is it possible to get your water from another supplier?