Proxmox does not have internet access, but CT's and VM's have

Hello

I have recently changed network adapter on my proxmox machine. I plugged a new eth adapter into the usb port, changed /etc/network/interfaces adapter and rebooted the machine. Everything was fine, but now I cannot access internet from proxmox console and cannot download any ct template, but all my ct's and vm's have internet access.

Where did I go wrong?
Can somebody help me to understand what is the problem and how to fix it?

thanks