@AlJose . Regarding firmware version, create a new thread and provide your firmware version. Firmware updates are done by TPG remotely. A moderator might not look at this thread now.
Also, ask about latency. Provide speed test results for your computer on ethernet, computer on wifi, and phone/tablet on wifi. If the 2 computer ping times are same but phone/tablet is slower, it must be just the wifi device is slower.
For comparison, I am on NBN25. I get the proper speed and my ping time on TPG speed test is 5 ms.