Ending that got so much backlash that the creator have to change it

Just like the title said, sometimes the creators make a controversial ending for their work which led to immense backlash that the creator have to go back and "fix" the ending.

Example: Jin Yong, one of the most influence Wuxia author once answer an interview and in it, he admitted that the ending of the novel "The Return of the Condor heroes" wasn't well-received by the fan and he had to modified the ending. The novel main story is about the forbidden love of the 2 main leads, one is the teacher and one is the student (which was taboo in ancient China because it was seen as incest). The original ending hs the female lead suicide so that the male lead would forget about her and move on which his life. After 16 years of waiting, the male lead would move on and marry the sister of the person who cut his arm. Naturally, the readers did not like despite how much shit the main couple went throught, they still can't be with each other and the female lead got the short end of the stick. After saw the response to the ending, Jin Yong rewrite it so that after 16 years, the main couple actually reunites and they live happily ever after. That ending while more universal accepted did make the later part of the novel a lot more clunky since it essentially make the new love interest character irrelevant and feel unnecessary.