Multiply command not working

I am putting the command "stackmultiplier.multiply 3" into the server console and reloading the mod, and it just isn't doing anything. Is there something I am missing?

I don't think you need to reload the plugin normally when using the command.

Hmm, well then have you got any ideas as to why it isn't working how it should?

Same problem for me...

oxide.grant group VIP1 stackmultiplier.multiply 15
Permission 'stackmultiplier.multiply' doesn't exist

What can i do?