It appears that King Charles was trying to let Prince Harry know that he is still upset with him.
Royal author Duncan Larcombe claimed that King Charles was “subtly punishing” his youngest son Prince Harry as he did not let him stay in Windsor Castle on his last visit to the UK.
The Duke of Sussex was in London last month for only a night to grace the WellChild Awards.
However, he was denied the righ to stay at the royal residences over "such short notice."
According to the royal author, the King is still "upset" with Harry over his bombshell revelations in his six-part Netflix docuseries Harry and Meghan, and his memoir Spare.
As per Larcombe, “It appears that King Charles’s approach towards Harry now is business as usual - 'if you want to see me you need to make an appointment.'”
He further elucidated that Harry will have to "get past the gray suits" and "jump through hoops" to talk to his father.
"It's very standoffish but I think that's a way that the King is subtly punishing his son." the author continued.
In the autobiography Spare, Harry called out the Queen as "villain" and accused her of leaking stories to the press to improve her own PR, saying that he and Prince William had begged their father not to marry her.
King Charles found these revelations against his wife really "hurtful" as Mr Larcombe explained to The Sun, “Harry has said some deeply hurtful things about Camilla, and yet the King will still correspond with his son, albeit not directly.”