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With so many dates to remember, it's easy to mess up birthdays, anniversaries, or holidays.
We've all been there, confusing two friends' birthdays because they were born on the same day in different months. Or forgetting the upcoming holiday was Memorial Day not Labor Day.
Or perhaps you pull a Sean Spicer and confuse 6 June for 7 December.
Spicer, the former White House Press Secretary under Donald Trump, tweeted on Wednesday 7 December acknowledging the sacrifice soldiers made when they stormed the beaches of Normandy, France on D-Day.
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"Today is Dday. It only lives in infamy if we remember and share the story of sacrifice with the next generation. #DDay," Spicer wrote.
The only problem- it's not D-Day.
Spicer, 51, confused D-Day which is on 6 June with Pearl Harbor Remembrance Day which is on 7 December.
According to Spicer's website, he holds a master’s degree in National Security and Strategic Studies from the US Naval War College and has served in the US Navy Reserve for over 20 years.
Shortly after he tweeted, several Twitter users pointed out to Spicer that he confused the two dates with one another.
"Sean Dday is June 6th... This is Pearl Harbor Day... Just an FYI," Michael wrote.
Spicer deleted his tweet and acknowledged his mistake with a quick apology.
However, Spicer's mistake did not go unnoticed as people mocked him for confusing the two dates.
"Sean Spicer's commitment to accuracy remains consistent," Philip Bump wrote.
"This is a dark horse contender for the worst tweet of all time lmao," Aaron Rupar tweeted.
Pearl Harbor Remembrance Day is the day the US remembers the 2,404 Americans who died in the attack on Pearl Harbor, Hawaii in 1941.
The day also marks when the US entered World War II by declaring war against Japan.
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