Warning: mysqli_connect(): (HY000/1045): Access denied for user 'root'@'localhost' (using password: NO) in code example

Example 1: mysqli::real_connect(): (HY000/1045): Access denied for user 'pma'@'localhost' (using password: NO)

$cfg['Servers'][$i]['port'] = '3307';

Example 2: mysqli_real_connect(): (HY000/1698): Access denied for user 'root'@'localhost'

ALTER USER 'root'@'localhost' IDENTIFIED BY 'mysql';