Welcome to the community!
There are different cause of Transfer/Speed Issue that you may experience.
- Sync Speed Issue, this speed issue is caused by a line fault on TPG (If you're with ADSL2+ or TPG-FTTB) or NBN's network (If you're with NBN service). Affecting all device(s) LAN/Wireless connected to the modem/router this may require a real-time test and investigation by our Technicians and Engineers.
- Wireless Transfer Rate Issue, this issue only affects the device(s) connected via Wi-Fi which can easily be fix by doing adjustment to the modem/router's settings.
- Speed/Transfer Issues, this issue is caused by possible loose modem/router connection setup. This can be fixed by re-seating Ethernet cable if the device(s) is connected via LAN, re-seating the modem/router to the wall socket or changing the phone cable used from modem/router to the socket.
Note: You will need to test multiple speed test when you change Ethernet,Phone Cable to identify the caused of speed issue.
- Speed Degradation caused by ongoing outage in your area.
We have created this article that can guide you on How to Check for NBN Network Outage - https://community.tpg.com.au/t5/Broadband-Internet/How-to-Check-for-NBN-Network-Outage/m-p/45557#M17....
In the event that you experience the issue on device(s) connected via Wi-Fi, we did an an article that you may find helpful this will guide you on how to improve your wireless connection at home.
Let us know how it will go. Cheers!