Do I have to pay the rent?

[Iqbal Sraon]

I was renting a property and was on month to month lease. More than a month ago, I found a new house to live for my family. So I texted my landlord on the phone, that I will be out of the rental property after 30 days. He agreed. On the 27th day I called my landlord on the phone and told him that I need to stay a month more on the property as there is a delay in the "closing" of my new house. He agreed. On the 29th day, I found out that I have to pay rent to the seller of my new house until my closing is done. In order that I won't get "double dipped" by my landlord and the seller, I called my landlord and told him that I have to move to the new house and I am getting out of the rental house on the previously agreed 30th day. I wonder if the landlord can charge me money for the verbal one month extension, I got from the landlord? Please help