Here are how to change WordPress user password using phpMyadmin,

Login into your phpMyadmin , if you use Cpanel you can access it below database menu

Go to your Wordpress database, and chose table with suffics “_users” then click “browse” to view database record in that table.

Chose “edit” for user that need password to change.

FIll password that you want to use on “user_pass” fields and from function chose “MD5″

And then press “Go”, now your WordPress password has changed, you can login to your WordPress with new password