Thanks for posting and welcome to the community. Sorry for the landline issue.
Changing to the phone service via cable is a government objective and this has to be completed by 2025, we are choosing to take the change over now to ensure all of our customers have been migrated prior to the current telephone exchange being closed down in 2025. The below links explain more;
https://www.virginmedia.com/help/landline/switchover and https://www.futureofvoice.co.uk/
From a system check you are still on a landline via the wallsocket.
On the system check, we've seen the landline is permanently engaged. Have you got any pieces of equipment connected to the phoneline? If so, can you try removing them for me to see if this solves the issue?
If no equipment or you've done this with no resolve, can you confirm are you connected via the Master socket or via an extension lead?
Also please try the below;
• Check the phone is seated in the base unit correctly & powered ON.
• Remove all other equipment connected to telephone sockets.
• Unplug the phone and check another phone directly into the main socket ensuring this is a VM socket and not one with a BT or Sky logo. If no alternative handset is available then ensure the original phone is plugged into the main socket with no other pieces of equipment being plugged in.
Let me know how you get on.