Seen a few similar posts.
I'm also unable to get through on the phone and seems you are directed here. Hope the peeps at Plusnet can help.
I seem to have an error with my bill. It is £40.98 and should be £23.95. Please can you fix this as soon as poss? As many people in the current situation, we are having to tighten our budget a lot due to work issues so would really appreciate this erroneous bill not going out of my account.