Choosing a default email account for my device
If you've set up more than one email account on your device, you need to select a default email account. When you write email, they'll automatically be sent from your default email account.
1. Find "Default Account"
Tap Mail, Contacts, Calendars.
Tap Default Account.
2. Select default email account
Tap the required email account to use it by default.
When the box next to an email account is ticked (V), the account is set as the default email account.
Tap the Home key to return to standby mode.