Connecting to 5 Ghz WiFi, whereas on 2.4 Ghz works just fine

Solution 1:

See what freq your Linux wireless card supports:

iwlist wlan0 freq # change wlan0 for your wireless network device name

Note the highest 5Ghz frequency supported. Higher channels work better than lower channels. Don't use any of the radar detection channels.

Go to your router and change the 5Ghz channel and change it from Auto to the highest rate found in the first step. Recheck your Linux connectivity.

Check your tablet for 5Ghz connectivity. Change the router 5Ghz channel if required, but staying within the supported wireless card range of your Linux machine.

Update #1:

In your iwlist wlp8s0 frequency, the only 5Ghz channels that match up are 36 through 48, so set your router's 5Ghz channel to one of those.

Look at /etc/default/crda. What country code do you see there?