I have just fixed my child theme.
The problem was it was using the following code in my function.php
wp_enqueue_style( 'hashone-style', get_stylesheet_uri(), array('jquery-bxslider', 'animate','font-awesome', 'owl-carousel', 'owl-theme', 'nivo-lightbox'), wp_get_theme()->get('Version') );
But the parent’s function.php changed in version 1.2.7 to
wp_enqueue_style('hashone-style', get_stylesheet_uri(), array(), '1.0');
So, I had to change the code to:
wp_enqueue_style( 'hashone-style', get_stylesheet_uri(), array(), wp_get_theme()->get('Version') );
I am using it in my child theme because I need that my server recognises when my style.css has changed.
Do you recommend another way to do it? If this code changes in the future, my child theme will have problems.