<?php if( have_posts() ): while( have_posts() ): the_post();?>not working code example

Example: wordpress have_posts not working

//As per my understandings of your issue:

//You are not querying posts you need to show. Use wp_query() to query your posts before loop.

$wp_query = new WP_Query(array('posts_per_page'=>-1));
while ($wp_query->have_posts()) : $wp_query->the_post();
    //your code here
endwhile;