Nevermind found a fix myself 🙂
I think the main reason was related to the fact that the “return format” was set to “Image URL” instead of “Image Array”.
After I changed that in my WordPress backend I now use the following code in my template and it gives me the alt tag and title tag of the image:
<?php
$image = get_sub_field('inside_the_customer_imgs');
printf( '<img src="%s" alt="%s" title="%s" />', $image['url'], $image['alt'], $image['title'] );
?>
