The call centre can take forever, and its only going to get worse as the current place - run by a company called firstsource, who have bases in Derby, and Livingstone ( amongst other UK places) has lost the contract with Sky for a much cheaper solution in India .
As for the overcharing:
If your bill has gone up by £3.50/month then you would have received an email to the same email address you have registered with Now broadband and is associated with your now broadband account.
This would have been along the lines of
subject: Your NOW Broadband Membership is changing
The confusion here is that the email is from Sky (Nows parent company) and would easily have been passed off as spam/unwanted sales guff - especially if you have had dealings with Sky at any point in your life.
but non the less it is what it is and that email would have the details of the £3.50 rise.
While the£3.50 price rise is unwelcome, for me Now broadband is still the cheapest deal out there
If your price has gone up significantly are you at the end of a "deal"?
You should have received an email towards the end of the first 12 months saying your minimum term contract is almost up, and in that will be some deals that are more expensive than what you are/were on.
At the bottom of this is a do nothing offer, where if you do nothing you will get a "special offer" that will be the same as the original price ( plus the £3.50 increase which it wont mention) for 12 months - with a date ie upto march 2024 - when this "offer" expires you may not receive a notification, and if you are not on the ball your first notification of this expiry will be a hefty increase on your bill - which can more than double.
Its a bit shady/crafty - but if you dont keep track of subscriptions/bills and when offers end you can end getting caught out - the best method that i find is to set a reminder in a calendar app such as google calendar about 6 weeks before an offer ends or subscription is due for renewal