Cannot change default FontAwesome5 icons

[forxer]

I'm trying to change the default icons but it doesn't seem to work.

PNotify.defaultModules.set(PNotifyFontAwesome5Fix, {});
PNotify.defaultModules.set(PNotifyFontAwesome5, {
    notice: 'fal fa-exclamation-circle',
    info: 'fal fa-info-circle',
    success: 'fal fa-check-circle',
    error: 'fal fa-exclamation-triangle',

    // Buttons Module
    closer: 'fal fa-times',
    sticker: 'fal',
    stuck: 'fa-play',
    unstuck: 'fa-pause',

    // Reference Module (Useful for other modules.)
    refresh: 'fal fa-sync'
});