Bug in the_excerpt() function

You can wrap your output in the has_excerpt function, this checks if the post has a custom excerpt.

if (!function_exists('sociality_excerpt_more')) {
    function sociality_excerpt_more($more) {
        if ( has_excerpt() ) {
            return $more . '&nbsp<a class="read-more p-color" rel="bookmark"  title="'. get_the_title() .'" href="'. get_permalink($post->ID) . '">'. esc_html__('View more','g5plus-handmade') .'<i class="pe-7s-right-arrow"></i></a>';
        } else {
            return $more;
        }
    }
    add_filter('the_excerpt', 'sociality_excerpt_more');
}