change translatable text programatically

<?php
//Rewrite any gettext field, this works for any translation for any plugin, check the $domain == 'dbem' to be more specific
function my_em_text_rewrites($translation, $orig, $domain) {
    switch ($orig) {
        case 'Booking is now fully paid and confirmed.' :
            $translation = 'your text here';
            break;
        case 'Repeat this again for what you want to translate (needs to be exactly same text in english)' :
            $translation = 'your text here';
            break;
        case 'You must allow us to collect and store your data in order for us to process your booking.' :
            $translation = 'translated - You must allow us to collect and store your data in order for us to process your booking.';
            break;
    }
    return $translation;
}
add_action ( 'gettext', 'my_em_text_rewrites', 1, 3 );