Error with experience addon (TTT)

I recently bought an experience addon which should show the specific level of a player on the top left corner (I think). The experience bar gets further if you kill the right person. But when I put the experience folder into my addon folder of my server and restart it you can’t see anything of this new addon. Further there is a permanent orange field which says “Script Error” or sth. on the top left corner. When I press F10 it says:

[ERROR] addons/experience/lua/core/cl_init.lua:24: attempt to index a 

nil value
  1. fn - addons/experience/lua/core/cl_init.lua:24
   2. unknown - addons/ulib/lua/ulib/shared/hook.lua:183

My luas are looking like so:

Could someone help me pls, I payed 10 bugs for this addon and I don’t want to give it up. :frowning:

Contact the author.

Apologies if I’ve misread here, but snipped your post as the creator probably won’t appreciate you posting code to a paid addon

Either way, please contact the author themselves or use Developer Discussion, as that’s where help belongs