non-event
noun [ C usually singular ] informal uk/ˌnɒn.ɪˈvent/ us/ˌnɑːn.ɪˈvent/
（尤指不如预期的）令人扫兴之事
a disappointing occasion that was not interesting, especially one that was expected to be exciting and important
The party turned out to be a non-event - barely anybody showed up. 结果聚会有点让人失望——几乎没什么人来参加。