This is because he is no longer a working member of the royal family. Harry was seen leaving Westminster Abbey shortly after his father's coronation and reportedly returned to his family in California to attend his son Prince Archie's birthday.
The palace had confirmed on April 12 that Harry would attend his father's crowning ceremony, but without his wife Meghan Markle and their two children, Prince Archie and Princess Lilibet.
However, Harry was not permitted to have an official role in the coronation due to his status as a non-working member of the family.
Harry's departure from the UK reflects his decision to step back from his role as a working member of the Royal family in January 2020 and move to America with Meghan Markle. Andrew, on the other hand, was effectively removed from his role as a working royal in January last year after his legal controversy with Virginia Roberts Giuffre.
During the coronation, both Harry and Andrew were seen leaving out of the Coronation Procession, which was in line with Buckingham Palace's confirmation that they would not have any formal role at the event. As a result of their non-working status, Harry was relegated to the third row at the coronation, while his family members appeared on the balcony at Buckingham Palace without him.
