As the mistake was done with the god Indra, he grants Hanuman a want that his entire body could be as powerful as Indra's Vajra, and that his Vajra can also not damage him. In addition to Indra other gods have also granted him needs: the God Agni granted Hanuman https://rivervlbrh.tkzblog.com/36754916/not-known-details-about-hanuman