Nature of address settings on SIP channel


I’m having problems when I set callerid on a call through a SIP provider I have, my callerid is prefixed with +CC(country code) of the country where the provider is, which is not the CC I’m setting. My provider says that I need to set the NOA(nature of address) to a different value, but I can’t find where to change this in the Asterisk config. Does any of you know this?