As the error was accomplished with the god Indra, he grants Hanuman a wish that his overall body will be as powerful as Indra's Vajra, Which his Vajra also can not hurt him. Along with Indra other gods have also granted him needs: the God Agni granted Hanuman a want https://hanumanmandirinaustralia.blogspot.com/2025/01/discovering-spiritual-heart-of.html