Connection not secure on some common websites

[Labandbro]

Hello!

I've been struggling with ( NET::ERR_CERT_AUTHORITY_INVALID ) Or "site not secure"

Even on common websites like "facebook" "instagram" and other big websites.'

Sometimes it works without any issues, but some days when trying to go to these websites it just says "site not secure" and then met by the code NET::ERR_CERT_AUTHORITY_INVALID

I can enter most websites but some of the common websites that I know is safe to enter, shows this code NET::ERR_CERT_AUTHORITY_INVALID, and site not secure.

I checked my WIFI and all seems to be fine, it also works without any problems my mobile.

I've cleaned cookies, and followed every step that miceosoft has provided for that particular issue, but it doesn't seem to work

How do I go from here? 

grateful for help or any tips!

Best regards 

Laban

[Labandbro]