How to delete only user meta value (not key) from usermeta table in wordpress?

Just remove the ID then.

$images = get_the_author_meta( 'images', $user->ID );
$images = explode(',',$images);

$images is an Array isn’t it? Then I hope this one can help you.
https://stackoverflow.com/questions/2448964/php-how-to-remove-specific-element-from-an-array

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)