@Mattwatson , if you service was activated from a retail store and you have not created an online account, use the sign in link at the upper right corner. On the sign in page will be a link to register an account. That link is to the chatbot for you to set up a support ticket to creating an online account.
@Mattwatson is this another account and you want to add to an existing My Account? With PM system, each number is tied to one My Account and tie to one email address. Multiple lines would need multiple email addresses to create different My Account login
Usually, if you activate a new account yourself online, you would have created an My Account already. Just in case you activate in store and did not create an My Account, or you forgotten the email you used, please open ticket with PM Support and they will sort it out for you