Prince Harry traveled solo to see his grandmother as she was dying, and that wasn’t by accident … Meghan Markle reportedly did not get an invite to be by her side.

Royal expert Katie Nicholl tells ET … it’s understood the Duchess of Sussex was not included in the reach-out to Harry when news came down that Queen Elizabeth was on her death bed, which explains why he made the voyage on his own.

Some speculated Meghan might’ve opted out as a courtesy or out of respect for Harry, but the report points to it being a decision made by higher powers within the Royal Family.

According to Nicholl … Meghan has said she’ll go to Balmoral Castle — where QE2 died — at another time. Remember, Meghan could’ve easily gone … she and Harry were already in the UK for work-related matters, and even canceled an event in London when they got the news.

In the end, Harry arrived at Balmoral after the Queen’s death was announced — King Charles and Queen Consort Camilla did make it in time, as they were already in Scotland for prior engagements. It’s unclear which other family members made it to Elizabeth’s side before she actually passed.

Keep in mind … Kate Middleton did not join Prince William in Scotland either — but she and William made it clear she was staying back with their 3 children at Windsor Castle.

As we reported … the Queen died at 96, and was the longest-serving monarch in British history.