Pagination with WP_query giving same items in each page

After digging for sometime I’ve managed to solve it. The issue was I wasn’t passing paged variable in the args. After passing it and tweaking the pagination logic it is working now.

<?php
$data = getData();

if(!empty($_REQUEST['posts'])){
    $args = array(
        'post_type' => 'post',
        'post_status' => 'publish',
        'posts_per_page' => 15,
        'category_name' => $_REQUEST['posts'],
        'paged' => $paged
    );
    
}else{
    $args = array(
        'post_type' => 'post',
        'post_status' => 'publish',
        'posts_per_page' => 15,
        'paged' => $paged
    );
}


$loop = new WP_Query($args);


?>

<style>

    /* Style for the disabled class */
.disabled {
    background-color: #ccc; /* Gray background color */
    color: #888 !important; /* Light gray text color */
    cursor: not-allowed; /* Change cursor to 'not allowed' */
    pointer-events: none; /* Make the button unclickable */
}

.blog_main .pagination .next, .blog_main .pagination .preview  {
    color: #000;
}

</style>
<div class="blog_main" data-aos="fade-up" data-aos-duration="500">
    <div class="container">
        <div class="filter-items">
            <div class="items">
                <div class="item <?php if(empty($_REQUEST['posts'])){echo 'active';} ?>">
                    <a href="<?php echo site_url('/blog')?>">Alla</a>
                </div>
                <div class="item <?php if($_REQUEST['posts'] == 'Blogg'){echo 'active';} ?>">
                    <a href="<?php echo site_url('/blog?posts=Blogg')?>">Blogg</a>
                </div>
                <div class="item <?php if($_REQUEST['posts'] == 'Nyheter'){echo 'active';} ?>">
                    <a href="<?php echo site_url('/blog?posts=Nyheter')?>">Nyheter</a>
                </div>
            </div>
        </div>
       
            <?php if ($loop->have_posts()) { ?>
                <div class="blog-container">
                    <?php while ($loop->have_posts()): $loop->the_post(); ?>
                        <div class="single-blog">
                            <a class="feature-image" href="<?php the_permalink()?>">
                                <?php echo get_the_post_thumbnail($post->ID, 'full') ? get_the_post_thumbnail($post->ID, 'full') : '<img loading="lazy" width="582" height="280" src="'.site_url( 'wp-content/uploads/2023/04/anse_lazio_stranden.jpeg' ).'" >' ?>
                            </a>
                            <div class="tags">
                                <span class="entry-date"><?php echo get_the_date(); ?></span>
                                <?php 
                                
                                $categories = get_the_category();
                                if ( ! empty( $categories ) ) {
                                    echo '<a href="' . esc_url( get_category_link( $categories[0]->term_id ) ) . '">' . esc_html( $categories[0]->name ) . '</a>';
                                }

                                ?>
                                <!-- <a href="">Nyheter</a> -->
                            </div>

                            <div class="title-section">
                                <a href="<?php the_permalink()?>">
                                    <h2><?php the_title()?></h2>
                                    <svg width="24" height="24" viewBox="0 0 24 24" fill="none" xmlns="http://www.w3.org/2000/svg">
                                        <path d="M7 17L17 7" stroke="#1D2635" stroke-width="2" stroke-linecap="round"
                                            stroke-linejoin="round" />
                                        <path d="M7 7H17V17" stroke="#1D2635" stroke-width="2" stroke-linecap="round"
                                            stroke-linejoin="round" />
                                    </svg>
                                </a>

                            </div>
                        </div>
                    <?php endwhile;?>
                </div>
       
    <div class="pagination">
    <?php
            $total_pages = $loop->max_num_pages;
            $current_page = max(1, get_query_var('paged'));

            $base_url = site_url('/blog');
            if (!empty($_REQUEST['posts'])) {
                $base_url .= '?posts=" . $_REQUEST["posts'];
            }

            $prev_page = ($current_page > 1) ? $current_page - 1 : 1;
            $next_page = ($current_page < $total_pages) ? $current_page + 1 : $total_pages;

            $prev_url = ($prev_page == 1) ? $base_url : add_query_arg('paged', $prev_page, $base_url);
            $next_url = ($next_page == $total_pages) ? $base_url : add_query_arg('paged', $next_page, $base_url);

            // Add CSS classes and disable buttons
            $prev_class = ($current_page == 1) ? 'disabled' : '';
            $next_class = ($current_page == $total_pages) ? 'disabled' : '';

            echo '<a href="' . esc_url($prev_url) . '" class="preview ' . $prev_class . '">Tidigare</a>';
            echo paginate_links(
                array(
                    'base' => str_replace(999999999, '%#%', esc_url(get_pagenum_link(999999999))),
                    'total' => $total_pages,
                    'current' => $current_page,
                    'format' => '?paged=%#%',
                    'show_all' => false,
                    'type' => 'list',
                    'end_size' => 2,
                    'mid_size' => 1,
                    'prev_next' => false,
                    'prev_text' => sprintf('<i></i> %1$s', __('Tidigare', 'text-domain')),
                    'next_text' => sprintf('%1$s <i></i>', __('Nästa', 'text-domain')),
                    'add_args' => false,
                    'add_fragment' => '',
                )
            );
            echo '<a href="' . esc_url($next_url) . '" class="next ' . $next_class . '">Nästa</a>';
            ?>
        </div>


        <?php } ?>

     </div>
</div>