WordPress /page/2 gives 404 when custom permalinks is set to %category%%postname%
My wordpress permalink settings,
Custom Structure: %category%%postname%.
Used next_posts_link() in custom theme in archive.php to get next posts link.
Next Page >> (display as expected)
But when i click the link it redirects correctly to mysite.com/my_category/page/2. But it results in 404.
Any advice would be appreciated.