The Duke and Duchess of Cambridge are in need of a new head of security after the policewoman responsible for protecting the royal family announced her resignation Tuesday.

Sarah Hamlin, assistant chief constable of Norfolk and Suffolk police force and head of the Royal Protection team for Prince William and his wife, Kate Middleton, revealed in a series of Twitter posts she would be leaving her position because she “no longer fit the org," The Telegraph reported. The 48-year-old, who landed her first job on the police force in 1986, was also responsible for protecting the Duke and Dutchess of Cornwall, or Prince Charles and his wife, Camilla.

Hamlin, a mother of two, has served as a detective inspector followed by a promotion to chief inspector, during which she oversaw urban sectors. She was a part of the team that launched the SOS Bus Project, a multi-agency initiative created to help young people in need in Norwich’s club land at night. She also worked as an editor for quarterly magazine British Association of women in Policing.

In a formal statement, Hamlin announced that her decision to resign comes as she plans for retirement.

“I have many fond memories and without doubt these are the best forces I could have wished to work with. I consider though that now is the right time for me to retire to spend more time with family and friends as I look to pursue my other dreams,” she explained.

Hamlin had been the target of several controversial tweets criticizing her leadership, Morning News USA reported. During her Twitter announcement, Hamlin noted one of the reasons she decided to resign was because her “values” no longer matching those of the force. However, she did not elaborate on the differences.

In a statement, Norfolk’s Chief Constable Simon Bailey praised Hamlin’s work over the past 30 years, saying Hamlin has “played a key role in helping us all to think differently about how we deliver policing in today’s online world.”