If Hanuman was so powerful, then how did Khumbkaran defeat him?

If Hanuman was so powerful, then how did Khumbkaran defeat him? Vijaya : According to Srimad Bhagvat Puran ; Kumbakarna was Vijaya - gate keeper of Vaikunta. Vaikunta : Well, Vaikunta is abode of Lord Sri Hari Vishnu. Curse : A curse by Sanath Kumar turned him and his brother Jaya into Kumbakarna and Ravana. Greatest : Kumbakarna was proverbially the most powerful demon ; when he was awake. Sleeping : But, he proverbially slept for six long months per year. Ears : He had large pot (Kumbha) like ears (Karan) . Thus, he was addressed as Kumbakarna. Battle : He had a fierce battle with Lord Hanuman ji. Lord Hanuman ji wounded him and Kumbakarna in anger struck Hanuman ji with a divine spear. Enraged Hanuman ji broke his spear and hit him. Aware : Unlike his brother Ravana ; Kumbakarna knew power of Lord Rama ; Lakshmana and Hanuman. He tried hard to convince his brother to resist war with Lord Rama. Loyalty : Finally, he decided to fight for his brother against Lord Rama. He knew that he would met his end at the hands of Lord Rama. Thus, he fought valiantly against Lord Rama. Facts : Hanuman ji is Rudransha ; Chiranjeevi (ever lining) and true Sita Rama devotee. Lord Hanuman has been blessed all deities ;planetary deities ; sages and divine souls. No one can ever defeat him in any manner. Thus, Kumbhakarna or any demon could not defeat Lord Hanuman ji. Prayer : Sri Ganeshaya Namah Jai Sri Sita Ram Narayan Sri Ram Jai Ram Jai Jai Ram Namo Parvatipataye Shiv Har Har Mahadev Shambo