I am returning a T-Mobile iPad air to the local Apple store. Should I keep the SIM card I activated on T-mobile for the free 200MB, or leave it in the air when I return it? I am not asking to steal anything. I just don't want my information leaked/given to someone else. If they wipe/discard the card, that is fine with me. As long as someone else doesn't end up getting my info, and racking up a bill to my name. Thank you! Will they deny the return if I keep the card?