First, file a new contect answer. Second, you can ask him to come another day. If the term of your lease runs past the day of your move and you have paid the rent, then he can't come in unless you consent, unless he is doing so for a proper purpose. What type of work is the landlord proposing to do? You should check your lease and NRS 118A. Also, if you are concerned about the landlord entering, definitely mention it in your new contest letter.
This is not specific legal or tax advice. My posting this answer is for general, non-specific information only. My answering this quesiton does not establish an attorney-client relationship,