If you own a Samsung Galaxy S10 or Note 10, chances are you are seeing the new update firmware message on your phone by now.
The simple main reason is:
That's right! As soon as your device is updated, the security patch date being introduced in firmwares of August 2021 or newer can no longer get unlocked remotely from carriers such as Sprint, Verizon, AT&T, T-Mobile, Metro PCS, Boost Mobile, Cricket & any other variants with their respective carrier.
We are sorry to say that you can no longer downgrade your device to a lower version. When a new bit is introduced, a rollback protection gets applied on the device, preventing it from ever going back to previous bits or firmware versions.
The only thing we can do at the moment is just wait until the current firmware is supported. AT&T variants or any other phone that prompts an unlock code when an invalid sim card is inserted can still be unlocked via Unlock Code Method.