Welcome to the Community!
Here's an article that can be of help to you.
Currently not all products have been added to the My TPG app. We are working on supporting more products in the future. For now only the following products are supported:
To view your mobile service online, you can use TPG My account via web browser for the meantime. www.tpg.com.au/myaccount
If you need further assistance, please PM me with your mobile number and full name.