As the error was done via the god Indra, he grants Hanuman a wish that his entire body can be as sturdy as Indra's Vajra, Which his Vajra can also not hurt him. Together with Indra other gods have also granted him wishes: the God Agni granted Hanuman a desire https://hindutemplesinaustralia.water.blog/2025/09/26/south-australias-hanuman-mandir-devotion-faith-unity/