Wifi disappeared on all in one Celeron desktop

[JJ881]

So tonight I was happily using my desktop to work on (via wifi) then my computer crashed...when I restarted it Wifi completely disappeared. When trying to open available networks, nothing comes up. Troubleshoot suggests connecting an ethernet cable but this is not possible as the router is downstairs!! I've tried searching options for help and the realtech adapter says it's working fine and doesn't need any updates. 
Any help would be greatly appreciated! I have to teach live lessons on Monday so really need to sort this issue asap.
TIA
From a very tired and stressed teacher.

[JJ881]

Spent two hours trying to resolve this issue last night...this morning it's back to normal and working fine.🙈

[Ekstra]

How did you do it? I have been trying to fix this for almost 3 months! Lol