Region : Argentina

Model : TL-WDR4300

Hardware Version : V1

Firmware Version :

ISP :

Hey guys, I have a problem here,

I just bought dual band router WDNR4300 with a PCIE Adapter WDN 4800.
After installation and setup, both my 2.4ghz and 5ghz was working fine.

After 4 hours, I went on to the router configuration to change the Network SSID and Password for my 5ghz,
However that caused me to be unable to be connected back to the 5ghz network. I kept reconfiguring my router for more than 10times,
toggling all the settings and eventually set the settings to Auto (for channel and bandwith)

On the Network connection window, there was my 5ghz network, but after i typed in the PSK, it says "failed to connect"

sometimes after trying to connect a few times, the 5ghz network would have red X on the side (replacing the signal bar) and
it says that the settings on my PC failed to meet the requirement of the router.

I have no idea what went wrong, it was working all so well initially and now this happens..
Please help!
Try to keep the words as laymen as possible, not really much of a IT person. ><
Thank you in advance for helping! :(