The British royals will have a scaled-down Christmas gathering amid fears of the Omicron variant.
The Duke and Duchess of Sussex have long felt "sidelined by the institution and were not a fundamental part of its future."
The protection officers were instructed not to put Maxwell's name in the visitors' book.
The Duchess of Sussex allegedly hired photographers to document her solo Christmas shopping trip in Montecito last week.
She is yet to meet her great-granddaughter Lilibet Diana, whom Prince Harry and Meghan Markle have named after her.
The Duchess of Sussex is born under the Leo sign, which makes her "sensitive" yet "fearless and passionate."
Prince Philip 'secretly' comforted Prince William at Diana's funeral when he thought cameras weren't there
New documentary says Prince Philip knew what it was like to be a member of a "dysfunctional family" and didn't want the same to happen to his grandsons.
The British monarch was planning to welcome around 50 relatives including senior members of the Firm for a pre-Christmas lunch at Windsor Castle this week.
The matter keeps the 95-year-old awake at night and she is "understandably very worried" about it.
The report comes after the Duchess was spotted Christmas shopping in the neighbourhood at some of her favourite stores.
A friend of Kate said that she and her husband Prince William have supported each other throughout the royal family's ongoing issues from Harry and Meghan.
One of the pictures showed Camilla helping a young boy in trying on a Welsh guard's famous bearskin cap.