A driving instructor who had his Instagram handle given to Prince Harry and Meghan said he feels "miffed but also slightly flattered".
Kevin Keiley, who lives in Worthing, had used the @sussexroyal name on the social media platform for the past three years to reflect his home county of Sussex and his love of Reading FC.
But on Tuesday he discovered Instagram had changed his handle without notifying him to @_sussexroyal_, which he describes as being "really lame".
Instagram is understood to have transferred the @sussexroyal account to Prince Harry and Meghan, due to inactivity on Kevin's account.
The social media platform told ITV News when an account is inactive they reassign the username in line with its policies.
However Mr Keiley said: "I was liking things so i don't understand how it was inactive."
"All they needed to do was tell me over email what is happening, that the royals want your name and I would've given it, but no, they went behind my back and did it without telling me."
The 55-year-old said he found out "sussexroyal" was no longer his handle after receiving a joking text from his son saying: "Haha, there's your handle gone then".
Mr Keiley added: "I've got nothing against the royals, I like Harry, he's one of us, it's just a shame Instagram went about it the way it did."
Prince Harry and Meghan's new account references their royal title - The Duke and Duchess of Sussex.
The royal couple broke the record for the fastest time to reach one million followers, after launching their own official account on Tuesday.
Meghan's best friend Jessica Mulroney was one of the first to follow the royal couple's account and posted two love hearts on their post.
Celebrities David Beckham and Gwyneth Paltrow are among some of the other 2.3 million followers.
The couple only follow 23 people, including Kensington Palace, Clarence House and Princess Eugenie, who launched her Instagram account last March.