Unfortunately the Ellipsis doesn't have a Reset Network Settings option, only the Factory Reset option.
If you've already tried restarting the tablet, have you also verified software is up-to-date on the tablet?
Is there any change if you disable mobile data first?
The only other thing I can think of aside from a Factory Reset would be to try restarting in Safe Mode.
Hold the power button until the power options appear on the screen, then press and hold on "Power Off" until "Reboot to Safe Mode" appears, then select that. Once the tablet restarts, see if you can connect to Wi-Fi in that mode. If you're still having the problem in Safe Mode, then the Factory Reset is the only other solution I know of. You can just restart the tablet as normal to get it back out of Safe Mode.