Please follow the below steps to reset a user's password in the Management Console:
On the left-side Menu navigate to Settings -> Users (located at the bottom of the page) -> Users tab -> Select the specific user by clicking on the Name:
In the User's account scroll to the bottom and select the "GENERATE PASSWORD" button. This will create a new random password that will replace the old one. Don't forget to 'Save' the changes once the password is generated, because only then the new password will be applied to the user's account and will become active:
You can copy and save the new password in a safe space or send it to the relevant user.