As the error was carried out via the god Indra, he grants Hanuman a wish that his 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 wishes: the God Agni granted Hanuman https://hanumanmandiradelaide.finance.blog/2024/06/14/embrace-serenity-and-culture-at-the-hanuman-mandir/