Pop up ads not resolved by parental controls

Uninstall all third party apps that are Cleaners/Optimizers/Anti-Virus

If you suspect you have installed adware/malware:

>System Preferences>Profiles click into it and then remove all the suspicious things from the list. (This Preference pane will not be present if no profiles found.)

Adware Removal Guide—Manual removal of : http://www.thesafemac.com/arg-identification/

or

Try running this trusted utility https://www.malwarebytes.com/mac/

also Verify you are not using SOCKS proxy:

>System Preferences>Networks>Advanced>Proxy uncheck the box

Adware/malware launch daemons can set SOCKS proxies without user participation.

(SOCKS is an Internet protocol that exchanges network packets between a client and server through a proxy server.)