I’d fight em and refuse to pay the extra on the bill. It’s not your responsibility to fix their fuck-up when they are the ones estimating and billing you. If they want their money they shouldve given you the correct bill the first time. It’s like getting a cheeseburger for $5, and then the restaurant realizes inflation exists and comes banging on your door for another $10 a month later.
Fun fact: I have literally never not fallen asleep watching an episode of x-files
(Might be due other underlying neurological issues, but shush)