As the mistake was carried out because of the god Indra, he grants Hanuman a desire that his entire body will be as sturdy as Indra's Vajra, and that his Vajra might also not damage him. In conjunction with Indra other gods have also granted him needs: the God Agni https://hanumantempleinsydney.blogspot.com/2024/07/the-spiritual-haven-of-hanuman-mandir.html