Hi. You did not enter the text to which this question refers, which makes it impossible for it to be answered. However, I will try and help in any way possible.
A traditional ending that has the feeling of "happily ever after" is the ending that gives the reader the certainty that no difficulty will settle down for the characters for the rest of their lives. However, a more modern ending is one that leaves room for the characters to face new problems and new adventures in the future, either because of attitudes they had in the past, or from poorly ended relationships, revenges and unfinished stories that these characters left throughout the narrative. In this case, to answer your question, you need to read the text to which the question refers and find loose ends, which can cause future difficulties for the characters, which establishes a more realistic and less idealized ending like "happily ever after ."