I work in a hotel, hotel usage

How would you say these sentences in the USA or English speaking country?

1 I need to disconnect the phone line of the room that are checking out tomorrow so that they can't make pgone calls at the last minute that we forget to bill.
2 I'll put you through to room 301. / I'll transfer you to room 301. / I'll connect you to room 301.
3 If he doesn't answer in his room, the call comes down to the front desk.

Thank you for everything