Welcome to the community!
There are different cause of Transfer/Speed Issue that you may experience.
We have created this article that can guide you on How to Check for NBN Network Outage
In this particular case, we ran an initial test to the service it shows getting a passing speed on the link, We did an article that you may find helpful, this will guide you on how to improve the wireless connection at home. See links below.
Should you need further assistance, feel free to search community for help or chat with us at https://www.tpg.com.au/support/contact/ and we'd be glad to assist you.