Samsung Galaxy S5 - How to unlink a Samsung account
You have change your primary email and as such you need to edit your Samsung Account on your smartphone.
In this article you will learn how to unlink the current Samsung account of your phone and create a new one.
Go to Settings > Accounts & Sync.
Tap on Samsung Account.
Scroll to the bottom of the page and tap on Remove Samsung Account.
A small notification will be displayed: You will lose all your data (messages, contacts, etc ...)
Tap on Continue.
Enter your password and follow the onscreen procedure to unlink the current Samsung account.
To create a new account:
Tap on Add account> Samsung Account> Accept the TOS.