i mean your laptop distance from your router plus is any obstacle and wall?, and dont please stack your router with BTU it will cause overheating,and you can try measure distance using your foot

LOL, pity you...
TM now came out idea kept play play with user so that they can give up and stay remain to maintain their ARPU? just idea...
You can if staff willing/able to help you, but still paying same price unless you got Ultimate then you can JIMAT RM30...
Thanks.
Now your WIFI myths is SOLVED.
You put your BTU and router in KICTHEN?

Do you know wifi is radio-wave? and so many kitchen peripherals affected your wifi?

CALL TM to relocate your equipment is the ONLY CHOICES.   

Since they already reset the BTU port. Just go ahead and buy new router. No point testing with WiFi if you can get full speed on LAN. Or borrow any other router from friend. No point testing using the same device over and over again. Your 5Ghz WiFi is screwed for some reason.

there is other choice BTW he can just buy a long cat5e cable and relocate his Router at higher place and there is no other electronic stuff nearby.
But only problem is he hate cable

Don’t bother. Have told him many times, and he keeps asking the same questions and talk about the same issues.

First, don't put your BTU and router besides the TV monitor. In some cases, the TV monitor will affect the router's wifi performance if put both of them side by side.

Second, don't put your router on the top of your BTU as the heat will damage your equipment in long term.

And third, like some other forumers said, if possible, don't put your router near to the kitchen.

LOL, eventually you still called TM like I've said very very early!!
It's your router and faulty cable caused it.

Unless you demanded 300Mbps+ for your smartphone, otherwise current setup is enough for you.

Default password inside the router box, should be default used.
BEWARE that, you might screw the settings if you are not familiar, BETTER STAY AWAY from it.!!

Good enough. Yes, use that password. But, you will need admin user and password details, for more advanced configuration. Get the DWA192. Your Cat5e cable must not be really Cat5e and instead Cat5, or quality is bad. Get one of the recommended brands on the 1st page.

I believe the real situation is like this:

Before the turbo, he wanted a good router, but StuartLee2015 is a stingy person. He knew Asus brand is good, but he was too stingy to spend money. Thus he asked for the cheapest asus router available which is RT-N12HP B1.

Back to few days ago when his account was turbo-ed.
He claimed he will purchase expensive router to max out his 500Mbps turbo such as DIR 878 and ASUS USB-AC53 adapter. (Everyone know StuartLee2015 is bullshitting by now)
When he learnt that his cable might be the issue, he went and bought the cheapest possible long cable without checking it for CAT5e certification. Not only that, he said he wanna buy DWA182 instead of USB-AC53.
He probably has only TWO real cat5e cables which was bundled with RGX4400 and ONU.

When the TM technician came after his begging, TM probably brought along DIR842 and normal cat5e (bundled with DIR842 instead of that cat6 bullshit) and demonstrated it is router problem as expected.
TM probably said to StuartLee2015 he could refresh his unifi contract duration and that DIR842 will be his.
Being the world most stingy person, StuartLee2015 immediately accepted the condition.

Indeed, next thing we know, he wanna ask how to remove that pesky @unifi suffix from his wifi SSID.  :lol2:

I find it unlikely since you already refreshed your contract and accepted that DIR842.

Anyway, DIR842 only has 2x2:2 configuration, so over 5Ghz with 2x2:2 wifi adapter, best case wifi speedtest will be 400Mbps without interference from neighbouring 5ghz hotspot.
Don't complain about not reaching 500Mbps again with wifi.

I'm so curious he will choose RM3xx bill shock or renew contract?

play around with wifi channel and channel width, after analysed nearby wifi hostpot. DIR850L max 2.4Ghz around 16xMbps so far...
I see, so you went for renew contract, but Technicians didn't charge you since it's on-site visiting?

Ah, the webkit/webview rendering engine something has cpu limitation when speedtest via web browser. Best to use speedtest apps on android.
~.~ Finally, he admitted it.....
Note: you will be charged for on site visit. 
edit: Still nobody gonna trust you will purchase new router.
Let see how will he respond to TM after his bill has additional RM53.......

Good for you. Finally solve the speed problem. I think it's sufficient. No point in spending unnecessary money.

The password should be on a sticker somewhere.

As for AC, if you're some distance away and behind a door or a wall, you can pretty much forget about high speeds. If you really want the speed, it's better to pull a cable and install a 5Ghz AP in your room.

The cable is probably just bad. I have a bad Cat5e which refuses to link at 1Gbps all the time and I have a Cat5 cable which links at 1Gbps but transfers at a max of 350Mbps.

You happy or not? Your room to router is like Pudu to Puchong.