“He gets ‘unavailable right now,’” a friend of Harry’s told People Magazine. “His calls go unanswered. He has tried to reach out about the King’s health, but those calls go unanswered too.”
The reason for this might be that King Charles has lost his trust in his younger son, according to a friend of the monarch who spoke to Sunday Times. “The problem for the King and other members of the family is the worry that if they have a chat with Harry, it will appear in Spare volume two. How do you regain the trust?” the friend said. “I don’t think Harry ever can. But from the conversations I’ve had with the King, I would never say their relationship is irreparable. The King’s capacity to forgive his son is undimmed. There are other members of the royal family who are much more weighted against Harry, that’s the problem.”

This isn’t the first time someone speaks of the King’s fear of Harry publishing another book.
“I can’t imagine that Harry would contemplate a follow up to Spare. He has indicated that he wants to move on: he has said his piece, vented his anger and faced the consequences,” BBC royal correspondent Jennie Bond said. “I don’t believe for a moment that he will revisit his grievances in a second book. There might be one about his work, or Invictus or the joys of parenthood but not about his issues with the past.”
She added: “If he did go there, then I am sure the response would be a continued dignified silence and a resounding crash as the Palace doors slammed on any hope of future reconciliation.”

On the other hand, royal commentator Kinsey Schofield believes that Harry is in fact capable of publishing a new book, one similar to Spare. On her program Kinsey Schofield Unfiltered, she said she believes that Prince Harry plans to release a second book when his father “inevitably” passes away and his brother, Prince William, ascends to the throne.
“I do think he would write about his family again. He was waiting to publish a book after [Queen Elizabeth died]. Originally they were saying there was going to be another publication after the [late] Queen died,” Schofield said.
“I suspect that maybe he would release a book after his father passed away. Especially if Prince William continues to keep him at arm’s length. Because what would the repercussions be if Prince William pushed you out of the fold?”
Only time will tell if Harry will make amends with his family.