Unhelpful arrogant staff

Home Connect has hidden costs on the Portal that dont get mentioned to you while on the telephone with the agent . Agent does not mention these costs , after 8 years we moved house and want to charge me a pro - rata for the new address even though I have paid for the full month on the old address , We were not notified of the pro-rata and now that i am cancelling they want to tell me that I have to pay a cancellation fee as i have a new 12 month contract . Non of these were told to me by the agent . There feedback is to go look on the portal . How can this be legal ?