Bug 437102

SUMMARY
In KDE Connect, all other things are working except when you use Find Device/Ring My Phone. It appears to be the case with Lineage OS based roms because on Stock Android 11, it works

STEPS TO REPRODUCE
1. Connect Device to Computer using KDE Connect
2. Press Ring My Phone

OBSERVED RESULT
Phone doesn't ring

EXPECTED RESULT
Phone should ring so a person can find it

SOFTWARE/OS VERSIONS
Windows: -
macOS: -
Linux/KDE Plasma: Kubuntu 21.04 / Kernel 5.11.0-17-generic
(available in About System)
KDE Plasma Version: 5.21.5
KDE Frameworks Version: 5.81.0
Qt Version: 5.15.2

ADDITIONAL INFORMATION
I used an app on my Android device to call the Find My Device activity so that I could record the log, which is given below


time: 1621009999543
msg: java.lang.NullPointerException: Attempt to invoke virtual method 'org.kde.kdeconnect.Device org.kde.kdeconnect.BackgroundService.getDevice(java.lang.String)' on a null object reference
stacktrace: java.lang.RuntimeException: Unable to start activity ComponentInfo{org.kde.kdeconnect_tp/org.kde.kdeconnect.Plugins.FindMyPhonePlugin.FindMyPhoneActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'org.kde.kdeconnect.Device org.kde.kdeconnect.BackgroundService.getDevice(java.lang.String)' on a null object reference
	at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3431)
	at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3595)
	at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:85)
	at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
	at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
	at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2066)
	at android.os.Handler.dispatchMessage(Handler.java:106)
	at android.os.Looper.loop(Looper.java:223)
	at android.app.ActivityThread.main(ActivityThread.java:7660)
	at java.lang.reflect.Method.invoke(Native Method)
	at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'org.kde.kdeconnect.Device org.kde.kdeconnect.BackgroundService.getDevice(java.lang.String)' on a null object reference
	at org.kde.kdeconnect.Plugins.FindMyPhonePlugin.FindMyPhoneActivity.onCreate(FindMyPhoneActivity.java:45)
	at android.app.Activity.performCreate(Activity.java:8000)
	at android.app.Activity.performCreate(Activity.java:7984)
	at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1309)
	at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3404)
	... 11 more