Hi, since I moved into my house I have had a blackbox in the centre of a wall with a cover plate on which looks awful. I have removed the cover and tested the cable and it seems to be dead. I can't find a switch anywhere that might supply it so I'm assuming that it's been disconnected at the other end for some reason. Would it be ok to remove the backbox, put a few wagos on the wires and then plaster over it?