I had an issue running Arch on a Surface Pro 3 a while back where Wifi would drop after some hours - I couldn’t ping or SSH in but the device itself could reach the internet.
I found a post mentioning Wifi power saving mode and disabled it, and it fixed the issue for me. I’ll look and see if I can’t find it, and update here if it looks relevant to you.
Also, I would definitely try with your laptop wired instead of wireless if you can.