A special power of attorney is required in sale of a piece of land through an agent

Dear PAO,

I have been living here in Japan since 2015. Last year, I executed a general power of attorney in favor of my cousin authorizing him to administer all my businesses and properties in the Philippines. I found out recently that my cousin is selling one of my properties to his friend. I did not authorize my cousin to sell any of my properties. Can he sell my property based on the general power of attorney I executed?