Please can you share your code? Is this on a single post or within a loop?
Assuming it’s set to array, your code should look like:
<?php
$image = get_field('review_icon');
if( !empty( $image ) ): ?>
<img src="<?php echo esc_url($image['url']); ?>" alt="<?php echo esc_attr($image['alt']); ?>" />
<?php endif; ?>
