Sim invalida liberado por At&t
AT&T me libero mi iPhone 6 Plus, solo que al colocar una sim de otro operador me indica que la Smin es inválida. Ya restaure el iPhony sigue sin activar.
iPhone 6 Plus, iOS 9.1, At&t unlocked
Did you already contact AT&T about that?
https://www.att.com/deviceunlock/#/
If your account meets requirements, the carrier can unlock certain models of iPhone so that they can work internationally. These models are still restricted to that carrier in the United States and won't work on any other U.S. carriers. Contact your carrier for more details.
copied from Wireless carrier support and features for iPhone in the United States and Canada - Apple Support
Unlock your iPhone
First, your carrier will need to process your unlock request. Then you'll back up, erase, and restore your iPhone to unlock it.
Start the process:
- See if your carrier offers unlocking. Only your carrier can unlock your iPhone.
- Contact your carrier and request an unlock. You might need to meet requirements to qualify for unlocking. After you submit the request to your carrier, it might take a few days to complete. Contact your carrier for the status of your unlock request.
- After your carrier confirms that your iPhone unlock has been processed, go to the next section.
If you have a SIM card from a carrier other than your current carrier, follow these steps:
- Remove your SIM card and insert the new SIM card.
- Complete the setup process.
If you don't have another SIM card you can use, follow these steps to complete the process:
- Back up your iPhone.
- When you have a backup, erase your iPhone.
- Restore your iPhone from the backup you just made.
Get help
Follow these steps if you have any issues or if you see this message in iTunes or on your device:"The SIM card inserted in this iPhone does not appear to be supported. Only compatible SIM cards from a supported carrier may be used to activate iPhone. Please insert the SIM card that came with your iPhone or visit a supported carrier store."
- Restore your iPhone to factory settings.
- Contact your carrier to make sure that the unlock was applied in your carrier's system.
- Restore your iPhone from a backup.
copied from How to unlock your iPhone for use with another carrier - Apple Support