Thank you. But I have WWDR intermediate installed in keychain now.I found a solution.https://support.securly.com/hc/en-us/articles/206980207-Why-do-i-get-the-This-root-certificate-is-not-trusted-error-Download the Securly certificate CRT file. (securly_ca_2034.crt)Navigate to Finder > Applications > Utilities > Keychain AccessSelect ‘System’ in the left-hand column.Open ‘File > Import Items’ and import the certificate file into the ‘System’ keychain.Now it works!