Changing the light switch
That sounds like a 3 way switch but I don’t think I have seen one labeled that way.  Other than the copper you only had 2 wires I think , I would connect 1 to L1 and the other to L  , I believe l is the common  for a 3 way and L1&amp; L2 are for the travelers , but for a single switch we just don’t use L2 . The switch won’t have on and off embossed on it if this is the case.
A photo would clear things up or the model # of the switch but I believe using L &amp; L1 will get it working.