Add user photo beside their posts in Profile Page posts tab

I want the user’s photo to show beside their post (to give it a bit of a Twitter feel) so I added the following code in the theme-child/ultimate-member/profile/posts-single.php

<?php echo get_avatar( get_the_author_meta( 'ID' ), 64 ); ?>

It is working the way I want it to, however, I noticed that when I click the load more posts button, the new loaded posts returns the gravatar default profile photo instead. Did I do something wrong or does it have something to do with the AJAX?

(Sorry, I am still learning and maybe shouldn’t touch too much stuff but I would love to know what might have caused it.)