WordPress \ Bootstrap 4 not building breadcrumbs correctly

the_title() echoes the title, by default. Use get_the_title() instead.

function get_breadcrumb() {

    echo '<nav aria-label="breadcrumb">';
    echo '<ol class="breadcrumb">';

    if(!is_home() && !is_front_page()) {
        echo '<li class="breadcrumb-item"><a href="'.home_url().'" rel="nofollow">Home</a></li>';
        if (is_page()) {
            echo '<li class="breadcrumb-item active" aria-current="page">"'.get_the_title().'"</li>';
        }
    }
    echo '</ol>';
    echo '</nav>';
}