Is there any other devices that is working fine with the router? if so, you may check whether the DVR obtains valid IP address then try to ping it on other computer to see whether they can...

What kind of device do you want to open ports for? the port forwarding is used to open ports for local device or server, it is normal that it only accepts internal IP address with the same subnet,...

I had similar problem before, I have to restart the computer to fix it, actually it can be system error or the adapter driver issue, you can try to update the driver of the wireless adapter, If that...

What is the model number of your router? Currently the router which supports IFTTT are Archer C5400 V2 US, Archer C3150, and Deco. Can refer to this link: http://www.tp-link.com/en/faq-1763.html

I has same problem before, but fixed it after I update to KASA 1.8.3 on my Android phone. Are you sure it is the latest one? If yes, you may send email to support.uk@tp-link.com for help.

When you turn it off on the app, is it grey out? And is the power light off on the smart plug? How about if you press the power button on the smart plug?