Welcome to TPG Community @Reazell!
You can update your payment details securely via https://www.tpg.com.au/myaccount.
Here's how:
https://community.tpg.com.au/t5/Broadband-Internet/Update-Credit-Card-or-Direct-Debit-payment-detail...
If you still require further assistance, let us have your TPG username or customer ID number via PM so we can lend a hand.
How do I private message (PM) in the community
https://community.tpg.com.au/t5/Welcome/How-do-I-private-message-PM-in-the-community/m-p/4093#M45
Regards,
Daisy_Dhen
