• The Duchess received her first dose of the COVID-19 vaccination on May 28
  • She attended soccer and tennis games last week
  • She was supposed to accompany Prince William for a thanksgiving event Monday 

Kate Middleton has been in self-isolation since Friday after she came in contact with a person who later tested positive for COVID-19, an official from Kensington Palace said Monday.

"Her Royal Highness is not experiencing any symptoms, but is following all relevant government guidelines and is self-isolating at home," a spokesperson said, CNN reported.

The Duchess of Cambridge canceled all her Monday engagements after she was advised to undergo self-isolation at home.

On May 29, the official Twitter handle of the Duke and Duchess of Cambridge shared a photo of Middleton receiving her first dose of the COVID-19 vaccine. She also thanked the officials and health workers who were working for the vaccination roll-out.

The 39-year old received her jab at London's Science Museum, a mass vaccination center near Kensington Palace. Middleton was vaccinated just a few weeks after Prince William received his jab, USA Today reported.

The Duke of Cambridge had tested positive last year. Prince Charles also tested positive for the virus last spring but has since recovered from it.

The U.K. government mandates self-isolation of 10 days for anyone who has had close contact with a positive person.

The Duchess is reportedly tested twice a week for COVID-19 as part of the royal household testing protocol.

She attended the Euro 2020 soccer tournament at Wembley Stadium on June 29 with Prince William and her oldest son, Prince George. She also attended the Wimbledon men's doubles tennis match Friday and held a staff meeting.

The Kensington official said the Duchess had followed the protocols as she wore a mask while preparing tea cakes in the kitchen.

On Monday morning, Prince William attended a thanksgiving service at St. Paul's Cathedral for the National Health Services (NHS). Middleton was originally scheduled to co-host an outdoor tea party for the NHS staff in celebration of the organization's 73rd anniversary. William and Middleton are patrons of NHS charities.

Duchess of Cambridge, Kate Middleton
Britain's Catherine, Duchess of Cambridge, visits Caerphilly Family Intervention Team (FIT) to learn about their work with children with emotional and behavioural difficulties, problems with family relationships and those who have or who are likely to self-harm, in Caerphilly, Wales, Britain, Feb. 22, 2017. Reuters