If you happen to own a Samsung Galaxy S7 and just recently purchased a brand spanking new AC wireless router (mine is a TP-Link Archer C2 AC750) you might be surprised to find out that your spiffy phone doesn’t detect the 5GHz access point while the cheap android box sitting under your tv can.
Well I was. Unlike the anonymous maker of the android box, Samsung, being a responsible manufacturer, is honoring your countries’ airwave regulation by limiting their phone to detect only the allowed 5GHz radio channels in your country. For Indonesia it’s channel 149 to 161, 20 MHz max, with max transmit power of 100 mW or 20 dBm. See if your country is listed here. If it’s not, google around.
In summary, what you have to do make your 5GHz access point work with your Galaxy S7 (or any Samsung devices) is to lock your access point to only broadcast using these specified channels.