Hi  @Fritzklyka,

If the router has no internet or internet is offline, please try the steps below:

Orange/Red Internet light on the router:

    1. Identify whether your router or ISP is the problem by connecting your PC directly to the modem to check the internet access. If the Internet is not working, Contact your ISP.

    2. Turn off the Modem and the Router, then power on the Router, Turn on the modem once the router is fully powered on.

    3. Log in to the web UI via http://tplinkwifi.net and follow the Quick Setup to set it up.

4. Please go to Advanced > Network > Internet > Mac Clone to clone the MAC address of your PC.  Please follow the FAQ: How do I configure MAC Address Clone on my TP-Link Archer Router?

Green Internet light on the router:

    1. Log in to the web management interface of the router (http://tplinkwifi.net), go to Advanced > Network > Internet > Advanced Settings > Change the DNS Servers into 1.1.1.1 and 8.8.8.8.

     2. Turn off the Modem and the Router, then power on the Router, Turn on the modem once the router is fully powered on.

  Get more detailed steps from the FAQ: What should I do if I cannot access the internet through Wi-Fi router?
 

For OpenVPN issue, please see How do I troubleshoot if the OpenVPN is not connecting

Please contact us again with the results and completed troubleshooting steps so we can help more effectively.

  @Joseph-TP 
Thanks for your effort to reply, with detailed instructions.
However I work as a Developer, running servers at home (with or without VPN etc) and has come to a dead end.
I have decided to buy another router.
This time a non Broadcom router that is supported by the OpenWRT or DD WRT community.
Thanks for your time.