Recently, when old iPhone users updated their phones to the iOS 15.7.1 RC version then their phones’ Face ID features stop working. Then after users set a new Face ID they receive the error message that Face ID is unavailable, please try again later.
As per the user-shared information they don’t see issues when their phone runs on the iOS 15.7 version. But now, when they update their phone to the iOS 15.7.1 version Face ID feature not working. iPhone 12 Pro, iPhone 13 Pro Max, and so on are devices that Face ID does not support after updating to iOS 15.7.1.
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The reason behind this error is not detected yet. As per MacRumors when they reached out to Apple that the full name of the iOS RC version is “Release Candidate”, which is neither a beta version nor a GM (“Golden Master”) version.
They also find out that the RC version is consistent with the updated content of the official version of iOS. Given that such bugs have appeared in older models such as the iPhone 12 Pro, Apple may release another version of the RC version before launching the official version to fix this.
Lastly, the company surely working on this error and soon release the solution for this in its next update till enjoy other features of this version.