As the error was performed via the god Indra, he grants Hanuman a would like that his system would be as strong as Indra's Vajra, Which his Vajra might also not hurt him. Along with Indra other gods have also granted him wishes: the God Agni granted Hanuman a want https://kylerhujnu.uzblog.net/the-best-side-of-hanuman-50561958