DNS failure

[pjaj]

This morning my chrome browser could not get access to any pages.
It showed the error
DNS_PROBE_FINISHED_NO_INTERNET
To cut a long story short, I fixed it by changing the ethernet port DNS servers to 8.8.8.8 etc.
It worked fine for a few hours then just crashed again whilst I was doing an online edit with Squarespace.
Changing the DNS servers to 1.1.1.1 did not work this time.
I ran various MS system repair and diagnostics, but no luck.
Swapped the ethernet cable, no joy.
WiFi is working.
Any ideas what I can do now.?

 

[pjaj]

Today I noticed that, whilst my android phone worked fine with WiFi, an iPad and an Amazon Fire Stick both failed. These have nothing to do with my PC's DNS settings or, for that matter, my PC at all. Also, booting the PC from 2 different memory sticks, one with Windows 7 and the other with Ubuntu still failed to connect via ethernet.
My VoIP phone (ethernet connected again) also stopped working today.
So it can't be the PC or Windows 10 or DNS settings after all.
Switching my fibre router off and on again a couple of times finally fixed it. All is back to normal.
But for how long? I'm contacting my ISP to discuss the problem.