Detaching NIC-end of file reached

Hi,

We are using Opennebula 5.6 in our environments. There is no problem with the installation. In our recent installation, we are facing some NIC issues. We can attach NIC to the VM but it cannot be detached even from the powered off VM. The error “end of file reached” and “Failed to open TCP connection to localhost:2633 (Connection refused - connect(2) for “localhost” port 2633)” pops up when we try to detach the NIC. The VM error in sunstone shows “Some ad-block extensions are known to filter the ‘/log?id=’ URL”.

Opennebula version: OpenNebula 5.6.1
Hypervisor: KVM
OS: Ubuntu 18.04

Can someone help us to solve this issue?

Thanks.