next_post_link() function for posts in the same category does not work

Question

I need to generate a button for the next post in the category and am using the following code

<?php next_post_link('%link','<span class="button-1">%title</span>',TRUE); ?>

But it includes posts from other categories even setting the $in_same_term parameter as TRUE and excluding other categories with the $excluded_terms parameter, modifying these parameters has no effect on the generated link, only the $format and $link parameters work.

I inserted this code into a content-news.php file which is called within the single.php.