Setting off a fashion frenzy ... the Duchess of Cambridge chats to Michelle Obama, whilst US President Barack Obama talks to Prince William. Photo: Reuters
A spokesman for the brand name stated "unprecedented traffic" had caused the technical glitch.
Kate, 29, has been photographed wearing Reiss on a number of events and is now some thing of an ambassador for the high street label.
For her first official royal engagement as a newlywed, she donned a innovative knee-length camel-coloured shift dress which she teamed with the Anya Hindmarch clutch. R. McCants #1 Jersey
Michelle Obama, left, wore a fuchsia 1950s-inspired gown having a blue overcoat and matching kitten heels when she met British Prime Minister David Cameron and his wife Samantha. Picture: Getty Pictures
But it was the 175 "Shola bandage" gown which sparked a web-based purchasing melt-down. G.Green #15 Home Jersey

Later on a post appeared on Twitter studying: "Due to unprecedented demand, Shola mania has crashed our website! We're endeavouring to bring the Reiss brand back to you ASAP!" G.Green #15 Road Jersey
The Duchess wore the brand in her official engagement portrait by Mario Testino. She has also been photographed sporting a Reiss coat whilst out with William.

Queen Elizabeth II, US President Barack Obama, his wife Michelle Obama and Prince Philip, Duke of Edinburgh pose within the Audio Room of Buckingham Palace. Picture: Getty Pictures
On the first working day of the Obamas' state visit towards the United kingdom, the first Lady made numerous outfit modifications.
In the morning at Buckingham Palace, Michelle Obama donned a knee length turquoise gown with embroidered flowers accompanied by a pink bolero.
The Queen picked a dress and coat ensemble by Peter Enrione.
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The Obamas in Britain
Michelle and Barack Obama meet Prince William and Catherine, Duchess of Cambridge at Buckingham Palace.