Welcome to Community!
Apologies if you were not able to reach our support queue yesterday. We have experienced an unplanned outage which affected both our phone and internet services.
Should you need to update your payment details, you can log in on My Account using your TPG username and password.
You may also check this Community article for more info: Update Credit Card or Direct Debit payment details or Re-try a Failed Payment securely online
Feel free to let us know should you require further assistance.