WIFI drop-outs on Lenovo 310 notebook

I am a Linux beginner and have installed Ubuntu Mate (16.4) alongside Win10 on a Lenovo Ideapad 310-151K.
I am currently having an issue with my WIFI dropping out and (mostly) not restarting until the notebook is rebooted. Connecting via cable is reliable and the WIFI works correctly in Win10. The Notebook WIFI card is listed as a Realtek RTL8821AE and (in Mate and Win10) it is connected to the 802.11ac network of a Netgear R2650ac router.

I have updated and run the upgrade commands (sudo apt update, sudo apt dist-upgrade) but these didn’t make a difference.
Also, I have been looking for solutions online and found the following instructions significantly reduced the frequency of the dropouts but didn’t completely fix the problem;
https://medium.com/@elmaxx/rtl8821ae-wifi-drivers-in-ubuntu-16-04-4c1286524afa .

Thanks in advance.

I have been attempting to resolve the problem ( Working on it) and I guess I broke it because now there isnt any wifi…