Too many cases here. A story or character starts out as a story or novel. It gets turned into a movie and becomes iconic, and that has become the standard even when it contradicts the original. Even (especially?) when the creator doesn’t like it.
Examples:
1.) Jules Verne’s Around the World in Eighty Days – I have several editions with a balloon on the cover, because that, more than anything, symbolizes this story. But there is NO balloon in Verne’s novel. He turned it into a long-running play, too, and there’s no balloon in the play, either. The balloon because permanently attached to the story when Mike Todd made it part of his Todd-AO Widescreen film version, and used it in the advertising. He said he knew he’d be criticized for it, but the ended up giving him the Verne Medal (for the film itself, I’m sure, not the balloon). Todd did it because he wanted to enliven the beginning of the film, which lacks a punch. And, no doubt, to give his widescreen cameras aerial vistas to shoot. Verne did write several sties and novels involving balloons, so it wasn’t thatr huge a stretch. Most film versions since have included a balloon, including Jacke Chan’s and David Tennant’s.
2.) The Overlook Hotel from Stephen King’s The Shining – Stephen King wasn’t really happy with the film Stanley Kubrick made from his novel, not surprisingly – it was radically changed from his story. But it was only his second film adaptation, and Kubrick was a highly renowned director. Years later they made a more faithful version that King himself has a cameo in, but no one remembers that version. They remember Kubrick’s Overlook Hotel. So when they made a film adaptation of Doctor Sleep, King’s sequel top The Shining, the director apologized to King, but said that he had to use the Kubrick version. They used the Kubrick version in the film Ready Player One, as well, but that’s not too surprising. They also used the carpet scheme from it as the carpeting in Sid’s house in the first Toy Story movie.
3.) I think I’ve mentioned this before, but the 1950s movies of three stories change the alien -spacecraft from its original appearance to the then-new popularity of Flying Saucers. The Thing from Another World** (based on John W. Campbell’s Who Goes There?**), The Day the Earth Stood Still (based on Harry Bates’ Farewell to the Master) and This Island Earth (based on Raymond F. Jones’ This Island Earth – they didn’t change the title that time) all had flying saucers as the alien ships. In Day the Earth Stood Still and This Island Earth the alien ships had been mostly featureless ovoids. In The Thing it was described as looking like a submarine. But flying saucers were the new thing, and just too cool not to use.
4.) Fu Manchu is described in Sax Rohmer’s original books as clean-shaven. But, through ten film actors and a TV series, he’s always been depicted with the long thin moustache that has come to be called a “Fu Manchu Moustache”
Lots of other examples, but I’ll give someone else a turn…
Remember, these aren’t simply cases where the book and its adaptation differ, but where the film version is completely different from the oroginal literary source and has become canonical and iconic.