HUD Error

Hello, I have a custom HUD, nearly done and finished. But when I look at doors an error appears.

The error is:



[ERROR] addons/darkrpmodification-master/lua/darkrp_modules/hudreplacement/cl_hudreplacement.lua:479: attempt to call method 'IsOwnable' (a nil value)
  1. DrawEntityDisplay - addons/darkrpmodification-master/lua/darkrp_modules/hudreplacement/cl_hudreplacement.lua:479
   2. unknown - addons/darkrpmodification-master/lua/darkrp_modules/hudreplacement/cl_hudreplacement.lua:489


The code part is: