Current call plans are PAYG ( pay as you go ) 700 mins and Unlimited, I would imagine you are on the PAYG option at 20.9p/minute, so a call that costs £5.50, is about 27 minutes, these call plan changes were communicated to customers quite some time ago.
Chances you are on an old broadband package as it’s possible to get broadband and line much cheaper , BT current deals ( for the most widely available speeds ) are £30 to £35 depending on the speed you want, if you don’t want a phone service at all you can deduct £5 from these prices ….as with almost everything , just sticking on what you have , after the minimum deal expires is generally the most expensive option, but that’s a universal truth, it not just your broadband supplier that brings in new ‘packages’ that make the legacy packages look poor value…it’s quite possible the deal you had was for a lower price for a period of time that then increased to £45 ish, in those cases you need to be aware of the date the price increases, so you can then renegotiate a new deal.
