Here is the OpenVPN settings you need configured on the C1200. https://www.tp-link.com/en/faq-1239.html For your DD-WRT router settings, it's suggested to contact the DD-WRT support.

Hi, You can refer to the link below to do the troubleshoot. https://www.tp-link.com/en/faq-2237.html

What's the model number of your router? Who is your ISP? Do you have internet when connected to the modem directly? How about the lights on the router?

Hi, Is your firmware the latest one? Is the deco app version the latest one? If not, please update the firmware and app version first. If you have configured the QoS function and have enabled high...

:-)

If you choose blacklist but no key word, which means in the time you select, you can go to internet. If you want to block internet in the time you select, you need choose whitelist and no key words...