Need to see a video with the latest Zoom update on trimming a recording

The blue start and stop is not working on trimming a recording. It is trimming the wrong portion or not doing it all. I do not see any videos on how to properly trim a recording. I just need to trim off the end of the recording and if I use the blue sliders it is only keeping that portion that I wanted to remove. Also AI support does not how to answer that question.