Can you fix this error? Sh_Pointshop

I'm trying to give me points but when I try, the console writes this error

[ERROR] addons/sh_pointshop/lua/pointshop/sv_main.lua:440: attempt to call method 'IsAdmin' (a nil value)

1. unknown - addons/sh_pointshop/lua/pointshop/sv_main.lua:440
2. unknown - lua/includes/modules/concommand.lua:54

Any ideas?

The cmd that im trying to exc is the following:sh_pointshop_add_standard_points "STEAMID" "POINTS"


PD:I have superadmin in the server, so I dont know what happens