I have a galaxy S3 that is jail broken. I bought the straight talk for t mobile and every thing as far as calling and sending text work, but it wont let me add a new APN. It just keeps saying restore default. I restore to default, tried restarting my phone, taking the battier out and turning it back on an trying again but it still says restore to default. How do i fix this, and add a new APN. Please help