diff --git a/nc_sky_isgen/init.lua b/nc_sky_isgen/init.lua
index d7ed6b7..adf71b7 100644
--- a/nc_sky_isgen/init.lua
+++ b/nc_sky_isgen/init.lua
@@ -398,7 +398,7 @@ minetest.register_globalstep(function(dt)
     for k,ref in pairs(minetest.get_connected_players()) do
       local is = get_standing_island(ref:get_player_name())
       if is and not minetest.check_player_privs(ref,{server = true}) then
-        cells[is.k].valid = false
+        is.valid = false
       end
       local p = ref:get_pos()
       if p.y < -128 then