Light switch problem

[teac532s]

Hi Folks

Decided to change my old living room switch for a nice new one. When I removed the old switch 2 of the wires were loose behind the switch ( probably not tighten the screws) The top wire was ok so I changed it first. When i went to wire the 2 remianig wires in I connected them to l1 and l2 but now my dining room and kitchen lights do not work. The old switch was 1 way and the new 1 is 2 way. Have I wired something wrong. All the wires in the switch (3) are covered in grey and can only make out hte top one (red underneath)I have tried the bottom 2 wires in both l12 and l2 but nothing. Also if old switch was 1 way where did the bottom 2 wires go if there was only 1 terminal.
Any help appreciated

 

[Spark123]

If the old one was a 1 way switch then I'd suspect both the wires will have shared the same hole . Put both of them in L1 and the other wire in C and see what happens. If it works but the switch works "upside down" then swop both the wires to L2.
Oh, and if you are changing it to a metal switch you need to ensure it is correctly earthed too, preferably with the earth wire going directly to the switch and a loop to the back box if metal.