VMware NSX
For vSphere Lifecycle Manager to get access to the NSX image, you must configure the cluster with a transport node profile. Hence, this is an expected behavior when vLCM is enabled on a vCenter Cluster; it is mandatory to have a TNP, and we cannot detach it.
Instead of detaching the TNP, please click 'Configure NSX' on the cluster level and select the desired TNP from the list.
This will reconfigure the hosts in the cluster based on the newly applied TNP.