two main culprits of this error (when the cert is indeed valid, like here) are..
your computer time is set wrong. year being way off usually.
malware/trojans.
Lesser possibility would be someone on your network trying to MITM your account info. (or a piece of software on someone elses machine they know nothing about)
... in any case. Do the default, check your time settings, check for malware/virus. Go from there.
If these do nothing. Try using a free vpn (hotspotshield, froot, cyberghost) and see if it happens. See if it happens on another PC on the same network.

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Fixed finally! Found out that my network settings had been changed to go through a proxy, simple enough, just turned off manual proxy settings and fixed! But 5 minutes later it was back and when I checked the manual proxy settings it had been turned back on again! Long story short I found a Background Process called "Client.exe" was behind it, reactivating the proxy settings on my computer. Deleted and now its all fine.

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I copied some stuff from Reddit, a guy was having the same problem and three of the solutions listed could be of help.

Ok so i am positive that My date and time are set correctly and i have scanned my pc with multiple antivirus softwares (malwarebytes, Panda) and chrome is still not working properly and i am not sure how to check if my network settings have been changed through a proxy, i cant seem to find this info. Any other ideas?
"edit" I checked my proxy settings and manual proxy is turned off.