My first time using a Chippie sim card. I occasionally get a call to go through, but mostly I get error messages saying " The number you are calling is unassigned or has been disconnected." Is there some setting I need to adjust? I got the sim card at Carrefour's Tech Center. I took it to the Chippie store in Marigot and he called a couple numbers and they went through so he just said there's nothing wrong with it. I researched calling methods for the various alternatives (Dutch side to French side cell, etc.) Am I missing something?