Why can't I see the blue trim handles in my Keynote audio recording?

I wish to trim off the start of recorded narration from my first Keynote slide.

Apple Support help files say, "disclosure arrow next to Edit Movie or Edit Audio", but I do not see this 'disclosure arrow' and the help file does not say where to find it.

I cannot seem to display the audio recording with the blue trim handles.

Help, please.

[Re-Titled by Moderator]