hello. My name is***** can help you with your question. I believe the card you are talking about would be your Sim card. This is the car that you put in the phone that allows you to get cellular service and data service through a service provider. You should be able to take out the Sim card that is currently in the phone and replace it with a Sim card from the provider of your choice as long as the phone was purchased outright, or has been paid off completely if it was on a contract. To tell you specifically where the card is in the phone, I would need to know the exact model of the phone. It is generally very easy to do this – usually it's in a small tray that you just have to eject using a pin or a paperclip.
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