I have been with TPG, and got ADSL2+. The speed i got was more like a dial up and everytime I was told that the cable distance is almost 3.8 km hence the speed of 2.5 Mbps was acceptable, so I started to wait eagerly for NBN. NBN wait is over, yipee! and started to get 40 Mbps download and 17 Upload. Sadly this lasted for a week, and was hit with the unplanned outage which lasted for few days. As soon as i thought everything is going to be fine and started to experience slowness so they replaced the modem. Internet worked fine for a month or so and again started to experience slowness.
The speed i have been getting on NBN since yesterday has fluctuating a lot and have getting as low as 2.8 Mbps down and 15 up.
I am putting too much trust on TPG that I have not switched provider since 2015?
Your modem is currently detecting a sync speed of 51Mbps from the line which you can confirm when you log in to your modem's user interface. It appears that the problem is getting the result to show up on your devices. It's possible that the trouble you may be having could be WIFI-related (signal interference, distance, weak signal) if you're using a WIFI connection only.
We would suggest running a speed test on a computer connected via Ethernet for us to narrow down the actual cause of the slower connection speed
You may check out these Community articles which may be related to the issue you are experiencing:
If the issue persists, let us have your best call back time so we can organise a member of our Technical team to contact you for assistance.