Thanks for sending us your details. We're able to confirm that we have the correct details and the factory reset for the modem/router has not yet been performed. Try to factory reset the modem/router.
You need push the pin-hole at the back of the modem/router for 3-5 seconds and wait for the lights to flash and release it. Let us know if the issue will persist and how it will go.
Thank you, @LeVuHoang.
Does the issue still persists?
If yes, have you tried clearing the cache and history on your browser?
What are the browsers that you've tried to access the modem interface?
Glad to hear that your main concern has been addressed at least.
As for the speed of the connection, since you mentioned that you're able to get a good result on the 5GHz band, it means that something is affecting the 2.4GHz only. This could be a possible congestion on the 2.4GH or a simple channel change may do the trick.
To change the channel, you may visit this link for the guide:Wireless Channel on your modem - what is it and why should I change it?
Let me know how it goes.
These Archer routers are plain rubbish. I have had nothing but problems with WIFI since I changed to this router. They are unstable and the signal strength at the other end of my home is hopless. It can only manage a link speed of 7 Mbps on 2.4G and about the same on 5Ghz band. My old Archer D7 had 3 external antenas where this one has all the antenas built in. Do TPG offer any higher powered routers other than the supplied 1600v ?
We're sad to know that you're having issue with the wireless connection of your modem/router. We did an article that you may find helpful; this will guide you on how to improve your wireless connection at home.
Feel free to visit the links below.
The modem we provide is optimised the setup to complement our specifically configured modem settings. We provide the modem for all our NBN plans as they are sold as an Internet & Home Phone Bundle. As the Home Phone component of your bundle is encrypted for security, you will need to use our modem if you are to make and receive phone calls.
In the event that the modem/router's wireless connection does not meet your satisfaction; you have the option to use a 3rd party modem/router for the service. If this is the case, we'll provide you with the settings required to configure the 3rd party modem with the settings required to access the internet.
Let us know how it will go and should you require further assistance.