Change the single event slug from ‘event’ to any word

Hello
I’m interested in changing the slug on the timely all-in-one calendar from “event” to “show”. I added in the child theme functions.php and I saved the permanent links. However the slug remain the same..any thoughs?

Thanks in advance.

function __ai1ec_custom_slug_name( $translations, $text, $domain ) {
if ( 
AI1EC_PLUGIN_NAME !== $domain ||
'show' !== $text 
) {     
return $translations;
}       
return 'ai1ec-event';
}       
add_filter( 'gettext', '__ai1ec_custom_slug_name', 10, 3 );