Yes same thing happened to me today.
Was offered a special offer Price for renewing at £22.99
Although confirmation of New Contracted price finally came through at £27.99 then claims following month will increase to £40.98. Ive attempted to phone to gain support to sort this, Plusnet unable to take any more calls, advised to call later tomorrow???? No scope to email any operative who is able to actually help, as on line chat does not have any powers to do anything of the kind. Sooooo utterly frustrated & angry Plusnet Claim to us Proud, More like rip us off!
I would like Plusnet to address this issue as soon as possible, otherwise i will take my custom elsewhere, whereby il be treated with more respect & as a valued customer. Shame on you Plusnet,