I managed to get the NPC runs the command for 4/5 times, but after that, he just doesn't respond when pressing E on him.

https://hastebin.com/oluvevopuh.json

Look in recon see if you are getting any errors before he stops responding.  if you reload your command plugin zbui.mm does he start working again?

Yes, if I reload the plugin, the command works for 3/4 times, but after that, it stops responding when pressing E. I have my cooldown set to 0 as well.
No errors in console

Witch plugin are you reloading to make it work again.