Multilingual posts title trimming not working

My blog post titles seem to be cut off at 9 characters in Japanese. I went ahead and tried to trim it in the PHP file but it’s not working:

<?php if ( $post_title ) : ?>
<h2 class=”post-title entry-title”>
“><?php echo wp_trim_words( get_the_title(), 155 ); ?>

Post titles seem to stick to 9 characters in Japanese.
is there anything I can do to make it work?