The duke and duchess will now fly back to Sydney and attend the Australian Geographic Society Awards at the Shangri-La Hotel on Friday evening.
While on their return flight to Sydney this morning, the pilot of their plane chose to abort the landing when the plane was only minutes away from the runway.
Sydney Airport confirmed the incident, which happened as the Royal couple returned to Australia following a Pacific tour taking in Fiji and Tonga.
The princess, a diplomat herself, called the visit by Harry and Meghan the "ultimate diplomacy".
It had been a long day for Prince Harry and his pregnant wife Meghan, who the previous night while wearing her Theia white evening gown, had smothered her bared arms in insect repellent, to ward off the possibility of mosquitoes carrying the unsafe zika virus.
An insider revealed that the nickname is used "affectionately" for the Duchess of Sussex as "they are rather alike". Naturally, the mom-to-be made a standout fashion choice, stepping off the plane in a long-sleeved red floral dress from Self-Portrait.
Before departing from Fiji the couple took part in the unveiling of a statue of British-Fijian war hero Talaiasi Labalaba, who lost his life defending his comrades in the Battle of Mirbat in 1972.
Airport staff carried a banner saying "Welcome Harry and Meghan" and schoolchildren who had been given the day off lined the roads between Fua'amotu airport and capital city Nuku'alofa to welcome the royal party.
Prince Harry and Meghan will also attend a cultural exhibition of Tongan handicrafts and travel to the oldest secondary school in the Pacific.
If so, it would mean Meghan, 37, giving birth to the Royal family's first pair of twins in over 500 years.
The couple arrived in Tonga from Fiji on Thursday and joined Princess Angelika and Prince Ata, King Tupou VI's son and daughter, at the Fa'onelua Centre.
Tonga, home to just 106,000 people, is also known as the friendly islands.
They are due back in Australia tonight for the final days of the Invictus Games, which Harry founded in 2014.