When I first got the new iPad at release, I tested my cell phone SIM inside it to see if my unlimited data plan would work. And it did. Fast forward a couple months later to now, and for whatever reason this same process won't work anymore. Not only can it not find 4G (only 3G), but it's asking me to activate a data plan whenever I try to access the internet. I checked the account settings, and it does correctly identity that there's already a mobile plan associated with the SIM and it can't be altered on the iPad. But I've no way to actually use my connection. What changed between then and now? I'm jailbroken, but I don't have anything installed that should interfere with that. Have there been similar cases such as mine? I really need to find a solution.