Thanks for your post and welcome to the forums. In order to view your bills, you will need to sign in using the primary email address on the account.
If you're unsure on what this is, speak to the team on 150 / 0345 454 1111 and they can help you reset this.
Bear in mind though that a secondary email address cannot be a primary address so you will need to create a new one.
Come back and let us know how the call goes.
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