Have single switch on landing upstairs and downstairs that switches on hall and landling light at the same time. In error cut cable upstairs which joins to ceiling rose in hallway and reconnected it "correctly" in 20amp junction box, however landline and hallway light stopped working. When looked in ceiling rose there was 1 red wire connected to the Blue Neutral side and 2 black wires joined together not connected to anything and also 1 red wire not connected to anything, and no wire apart from light brown wire connected to neutral. Tried connecting wires back up, however unsure where go to ie live, neutral or other. Have got 4 cables coming into the ceiling rose, containing 2 red wires and 2 black wires, other wires are earth green wires. At moment have wired the two black wires and red wire into the neutral and the downstairs swich switches on the hall light however does not switch on the upstairs landing light like it should. The landing switch does not do anything now. Any suggestions? The hall switch has 1 red and 2 black wires coming into it and the landing switch has 2 red and 1 black coming into it. Need to get both landing and hall switch to operate as 1 ie switch both lights on at same time or off.