[Xiaomi Mi Mix 2 ROMs, Kernels, Recoveries, & Other] bluedragon14:
Looking at the exception in logcat,

10-12 10:02:18.027 24172 24172 E Zygote : java.lang.RuntimeException: Error receiving broadcast Intent { act=android.net.conn.CONNECTIVITY_CHANGE flg=0x4200010 (has extras) } in com.android.server.NetworkManagementService$1@4068af3
10-12 10:02:18.027 24172 24172 E Zygote :	at android.app.LoadedApk$ReceiverDispatcher$Args.lambda$getRunnable$0(LoadedApk.java:1401)
10-12 10:02:18.027 24172 24172 E Zygote :	at android.app.-$$Lambda$LoadedApk$ReceiverDispatcher$Args$_BumDX2UKsnxLVrE6UJsJZkotuA.run(Unknown Source:2)
10-12 10:02:18.027 24172 24172 E Zygote :	at android.os.Handler.handleCallback(Handler.java:873)
10-12 10:02:18.027 24172 24172 E Zygote :	at android.os.Handler.dispatchMessage(Handler.java:99)
10-12 10:02:18.027 24172 24172 E Zygote :	at android.os.Looper.loop(Looper.java:193)
10-12 10:02:18.027 24172 24172 E Zygote :	at com.android.server.SystemServer.run(SystemServer.java:487)
10-12 10:02:18.027 24172 24172 E Zygote :	at com.android.server.SystemServer.main(SystemServer.java:309)
10-12 10:02:18.027 24172 24172 E Zygote :	at java.lang.reflect.Method.invoke(Native Method)
10-12 10:02:18.027 24172 24172 E Zygote :	at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:495)
10-12 10:02:18.027 24172 24172 E Zygote :	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:838)
10-12 10:02:18.027 24172 24172 E Zygote : Caused by: java.lang.IllegalArgumentException: command '127 bandwidth addrestrictappsondata rmnet_data1 10006' failed with '500 127 Unknown bandwidth cmd'
10-12 10:02:18.027 24172 24172 E Zygote :	at com.android.server.NetworkManagementService.restrictAppOnData(NetworkManagementService.java:1861)
10-12 10:02:18.027 24172 24172 E Zygote :	at com.android.server.NetworkManagementService.processPendingDataRestrictRequests(NetworkManagementService.java:1929)
10-12 10:02:18.027 24172 24172 E Zygote :	at com.android.server.NetworkManagementService.access$200(NetworkManagementService.java:142)
10-12 10:02:18.027 24172 24172 E Zygote :	at com.android.server.NetworkManagementService$1.onReceive(NetworkManagementService.java:437)
10-12 10:02:18.027 24172 24172 E Zygote :	at android.app.LoadedApk$ReceiverDispatcher$Args.lambda$getRunnable$0(LoadedApk.java:1391)
10-12 10:02:18.027 24172 24172 E Zygote :	... 9 more
10-12 10:02:18.027 24172 24172 E Zygote : Caused by: com.android.server.NativeDaemonConnector$NativeDaemonArgumentException: command '127 bandwidth addrestrictappsondata rmnet_data1 10006' failed with '500 127 Unknown bandwidth cmd'
10-12 10:02:18.027 24172 24172 E Zygote :	at com.android.server.NativeDaemonConnector.executeForList(NativeDaemonConnector.java:512)
10-12 10:02:18.027 24172 24172 E Zygote :	at com.android.server.NativeDaemonConnector.execute(NativeDaemonConnector.java:411)
10-12 10:02:18.027 24172 24172 E Zygote :	at com.android.server.NativeDaemonConnector.execute(NativeDaemonConnector.java:406)
10-12 10:02:18.027 24172 24172 E Zygote :	at com.android.server.NetworkManagementService.restrictAppOnData(NetworkManagementService.java:1859)
10-12 10:02:18.027 24172 24172 E Zygote :	... 13 more

the problem appears to be with something using NativeDaemonConnector.java and NetworkManagementService.java files. I would recommend sticking with the Aug build of RR, or switching to LOS or PE.