All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
If a child was born circumcised, nothing is required in his case. The Maaliki Scholar Al-Kharashi clarified,“If a child was born circumcised, some scholars said: pass the razor blade over his private parts to cut off any remnants. Other scholars said that such a person has been relieved from circumcision and nothing should be done.”
Perhaps the first opinion is more likely to be the predominant opinion, especially if the person in question has already reached puberty.
We do not know of any evidence proving that if a child is born circumcised, he was circumcised by the angels.
Allaah Knows best.