Cannot amplify volume

[Audacity 2.3.0]

I’ve imported a Wave file and I need to make parts of it louder. But the Amplify effect’s OK button is disabled.
I’ve read in the forum that if the imported waveform is touching the upper and lower sides of its track, Amplify can’t work. It does touch them, but how can I amplify it then?


It is impossible to amplify those peaks any higher without causing distortion.
To make the track sound louder, you need to reduce those peaks to that there is room to increase the average level. To do that, try the “Limiter” effect.