Some Nokia 7 Plus users who are presently testing the Android P beta have started facing issues after installing the June Android security update. The affected users have reported their problems on Nokia Community forum. However, HMD Global hasn't announced any official fix. Companies generally recommend users to use a public release over a beta build to avoid issues and flaws on devices. Therefore, the only solution that appears to be available for the affected users is to move back to the publicly available Android 8.1 Oreo build in order to download the latest Android security patch.
As per the reports available on the Nokia Community forum, a group of Nokia 7 Plus users testing the latest Android P beta have started receiving error messages after installing the June Android security patch. Some other users on the forum highlighted that they aren't able to use the handset after installing the update as it freezes at the boot screen. "After installing [the] security patch and finishing reboot, it showed .com.androidphone stopped working," one of the affected users posted on the official forum.
Most of the users believe that the June Android security patch that comes in 1.3GB of size essentially downgrades the software back to Android Oreo. XDA Developers speculates that this is what is causing crashes, with apps force closing because their data is meant for a "newer version of Android". Importantly, the rollback package on the Android P install page can't be installed as the June update comes as a newer update against the beta build.
Having said that, you can resolve the issue after restoring your Nokia 7 Plus if you're facing any issues after installing the June Android security patch. You need to factory reset the device back to Android 8.1 Oreo via the recovery menu and then install the security update.
Last week, some Pixel 2 XL users had reported that they are experiencing a lag in unlocking the screen after installing the June Android security update. The official Google account on Reddit responded to the user posts with an acknowledgment and promised an update to fix the issue.
Launched early this month, the June Android security update includes six functional updates and as many as 66 security fixes. It also improved antenna switching behaviour and fixed issues with the proximity sensor.