Landlord threatening to charge penalty even though I've given notice

Hi, The below clause is part of my agreement. My agreement starts on 1 Feb 2020. I've given 1 month written notice to my landlady that I wish to terminate this contract on 1 Feb 2021 i.e. my last date will be 31 December 2021. My landlady is threatening to charge 2 months rent from my deposit if I terminate the contract. Is that legal? If I change the last date as 1 Feb (termination 2 Feb), can then landlady charge for the entire month? There is no clause in the rent agreement stating that I need to stay the entire month. Notwithstanding anything herein contained, however subject to provision clause 6 hereinafter mentioned, the licensor/licensee shall be entitled to terminate this agreement at any time from the date of commencement of this licence by giving the licensor/licensee one month prior written notice. The licensor/licensee at his discretion may allow the licensee/licensor to terminate the agreement within 12 months in which case the licensor/licensee shall pay an additional compensation equivalent to two months compensation as damages. The licensor/licensee shall be entitled to terminate this agreement anytime