SERVICE_FORBIDDEN when adding a new category

Hello when I try to access to service category->add with a free account
I get:
The access to service [category->add] is forbidden

But when I try with payment account works fine, is there any restriction related with free account?

Thanks

I get the same result with Test Console http://www.kaltura.com/api_v3/testme/index.php

Thanks! I solved I put the secret instead of adminSecret

Thanks!