Renewal
Extend it, and change nothing else
A renewal adds time to the line you already have. The server address, username and password stay exactly as they are, so nobody has to touch a television in another country or talk a relative through anything.
Use the email address you ordered with the first time. That is what ties the renewal to your existing subscription. Paying under a different address creates a second line rather than extending the one you have, which is the usual reason somebody pays and finds a family member still cut off.
Identical login details No device needs touching Time added to what is left
Not sure which address you used, or which of two accounts is the live one? Message support and we will find it, and merge the two if that is what happened.