@KJ1 

Apologies for the very late reply. Finally had time and opportunity to try it out: it worked! 

Thanks so much for your help. 

@TonyDo having the same issue....already done all the setting but still cannot connect using cable

@rashidi 

I followed @KJ1 solution and that worked. Note that I didn't use the exact settings he used but followed his process to find and use the relevant settings (i.e. numbers) for me. 

@TonyDoi already reset and set back the deco and off the IPTV setting...when i connect the second port to my android box i can get internet access...but when i connect using my laptop is enable but no internet.

my deco is set as 1 router and 1 AP......any idea?

.

@KJ1 it is working and this is the solution if need to enable the other port for other devices. Make sure u first disable the previous VLAN setting (e.g. Maxis 1, TM etc), then only setup the customize VLAN from scratch but inputing the VLAN ID, which is normally 621 in mosr cases.

After that, make sure you restart the TP Link main router to take effect. That should work.

@KJ1 Hi ! My iptv/lan has no "mode" to set up. It says my device device has to connect deco wifi network? Whats thats? Also if i disable iptv/vlan it has no internet connection. Really need your help guys 😅

@Azeemsyuk Hi! Your iphone needs to be connected to this wifi before you can change this settings. And my guess is you're trying to connect laptop to internet using LAN cable? If that's the case, press the ISP profile and select custom. Type 500 into the internet VLAN ID and 0 to the priority. Just switch off the IPTV fields. Hope it helps!