Mandela effect could be real or just collectively misremembering things? But there are indeed some strong real-life examples.
1. Was there 4 or 6 seats in JFK's car when he was assassinated? There are very old photos and footages showing its 4 seats but there are also other high pixel photos showing its 6 seats.
2. Publishers clearing house says on its website that they never hired Ed Mcmahon, the guy that everyone remembers giving out publishers clearing house checks on TV!
(3:52) is the Ed McMahon part
https://www.youtube.com/watch?v=QkjrE1TCvpA
You guys must have more, welcome to add to the list.