ERROR 1698 (28000): Access denied for user 'root'@'localhost' - Mysql Server

I was using ubuntu 18 and simply installed MySQL (password:root) with the following commands.

sudo apt install mysql-server
sudo mysql_secure_installation

When I tried to log in with the normal ubuntu user it was throwing me this issue.

ERROR 1698 (28000): Access denied for user 'root'@'localhost'

But I was able to login to MySQL via the super user. Using the following commands I was able to log in via a normal user.

sudo mysql

ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'root';
exit;

Then you should be able to login to Mysql with the normal account.