Cloud Firestore Backend が応答しない

前提・実現したいこと

Firebaseと連動して辞書アプリを作成しています。
Flutter, Dart, およびAndroid Studioをアップデートした後から、下記のエラーが発生しており、それを取り除く方法を探しています。

発生している問題・エラーメッセージ

W/Firestore(14554): (21.3.0) [OnlineStateTracker]: Could not reach Cloud Firestore backend. Backend didn't respond within 10 seconds

該当のソースコード

Consoleの部分です。(文字数制限により途中から)

Dart
1W/.dictionary.ap(14554): Verification of void com.google.firebase.auth.api.internal.zzea.zza(com.google.android.gms.internal.firebase_auth.zzbt, com.google.firebase.auth.api.internal.zzdu) took 3.038s
2W/.dictionary.ap(14554): Verification of void com.google.firebase.auth.api.internal.zzea.zza(com.google.android.gms.internal.firebase_auth.zzbx, com.google.firebase.auth.api.internal.zzdu) took 2.221s
3W/.dictionary.ap(14554): Verification of void com.google.firebase.auth.api.internal.zzea.zza(com.google.android.gms.internal.firebase_auth.zzct, com.google.firebase.auth.api.internal.zzdu) took 226.229ms
4I/.dictionary.ap(14554): Background concurrent copying GC freed 13054(660KB) AllocSpace objects, 15(704KB) LOS objects, 49% free, 1903KB/3807KB, paused 54.948ms total 2.846s
5I/FA      (14554): Tag Manager is not found and thus will not be used
6D/EGL_emulation(14554): eglMakeCurrent: 0xe937f6a0: ver 3 0 (tinfo 0xd2c674d0)
7D/eglCodecCommon(14554): setVertexArrayObject: set vao to 0 (0) 1 0
8I/OpenGLRenderer(14554): Davey! duration=25747ms; Flags=1, IntendedVsync=20501971948884, Vsync=20501971948884, OldestInputEvent=9223372036854775807, NewestInputEvent=0, HandleInputStart=20501974323538, AnimationStart=20501974385538, PerformTraversalsStart=20501974432538, DrawStart=20526020391538, SyncQueued=20526045706538, SyncStart=20526051548538, IssueDrawCommandsStart=20526053772538, SwapBuffers=20527099237538, FrameCompleted=20527725670538, DequeueBufferDuration=44633000, QueueBufferDuration=12102000, 
9I/Choreographer(14554): Skipped 1548 frames!  The application may be doing too much work on its main thread.
10W/FirebaseInstanceId(14554): Token retrieval failed without exception message. Will retry token retrieval
11D/EGL_emulation(14554): eglMakeCurrent: 0xde1c9ec0: ver 3 0 (tinfo 0xbd813450)
12D/eglCodecCommon(14554): setVertexArrayObject: set vao to 0 (0) 1 0
13W/.dictionary.ap(14554): Unsupported class loader
14W/DynamiteModule(14554): Local module descriptor class for providerinstaller not found.
15W/.dictionary.ap(14554): Verification of void io.grpc.MethodDescriptor$MethodType.<clinit>() took 555.033ms
16W/.dictionary.ap(14554): Verification of cq cp.asInterface(android.os.IBinder) took 494.476ms
17I/DynamiteModule(14554): Considering local module com.google.android.gms.flags:3 and remote module com.google.android.gms.flags:3
18I/DynamiteModule(14554): Selected local version of com.google.android.gms.flags
19I/DynamiteModule(14554): Considering local module providerinstaller:0 and remote module providerinstaller:0
20W/ProviderInstaller(14554): Failed to load providerinstaller module: No acceptable module found. Local version is 0 and remote version is 0.
21W/.dictionary.ap(14554): Accessing hidden method Lsun/misc/Unsafe;->getLong(Ljava/lang/Object;J)J (greylist,core-platform-api, linking, allowed)
22W/.dictionary.ap(14554): Accessing hidden method Lsun/misc/Unsafe;->arrayBaseOffset(Ljava/lang/Class;)I (greylist,core-platform-api, linking, allowed)
23W/.dictionary.ap(14554): Accessing hidden method Lsun/misc/Unsafe;->copyMemory(JJJ)V (greylist, linking, allowed)
24W/.dictionary.ap(14554): Accessing hidden method Lsun/misc/Unsafe;->objectFieldOffset(Ljava/lang/reflect/Field;)J (greylist,core-platform-api, linking, allowed)
25W/.dictionary.ap(14554): Accessing hidden method Lsun/misc/Unsafe;->getByte(J)B (greylist,core-platform-api, linking, allowed)
26W/.dictionary.ap(14554): Accessing hidden method Lsun/misc/Unsafe;->getByte(Ljava/lang/Object;J)B (greylist,core-platform-api, linking, allowed)
27W/.dictionary.ap(14554): Accessing hidden method Lsun/misc/Unsafe;->getLong(J)J (greylist,core-platform-api, linking, allowed)
28W/.dictionary.ap(14554): Accessing hidden method Lsun/misc/Unsafe;->putByte(JB)V (greylist,core-platform-api, linking, allowed)
29W/.dictionary.ap(14554): Accessing hidden method Lsun/misc/Unsafe;->putByte(Ljava/lang/Object;JB)V (greylist,core-platform-api, linking, allowed)
30W/.dictionary.ap(14554): Accessing hidden method Lsun/misc/Unsafe;->getLong(Ljava/lang/Object;J)J (greylist,core-platform-api, reflection, allowed)
31W/.dictionary.ap(14554): Accessing hidden method Lsun/misc/Unsafe;->getLong(Ljava/lang/Object;J)J (greylist,core-platform-api, reflection, allowed)
32W/.dictionary.ap(14554): Accessing hidden field Ljava/nio/Buffer;->address:J (greylist, reflection, allowed)
33W/BiChannelGoogleApi(14554): [FirebaseAuth: ] getGoogleApiForMethod() returned Gms: com.google.firebase.auth.api.internal.zzak@25f8c60
34I/.dictionary.ap(14554): The ClassLoaderContext is a special shared library.
35I/.dictionary.ap(14554): The ClassLoaderContext is a special shared library.
36I/.dictionary.ap(14554): The ClassLoaderContext is a special shared library.
37I/.dictionary.ap(14554): Background young concurrent copying GC freed 11424(807KB) AllocSpace objects, 8(352KB) LOS objects, 41% free, 2219KB/3807KB, paused 1.504ms total 291.869ms
38V/NativeCrypto(14554): Registering com/google/android/gms/org/conscrypt/NativeCrypto's 286 native methods...
39W/.dictionary.ap(14554): Accessing hidden method Ljava/security/spec/ECParameterSpec;->getCurveName()Ljava/lang/String; (greylist, reflection, allowed)
40D/NetworkSecurityConfig(14554): No Network Security Config specified, using platform default
41I/ProviderInstaller(14554): Installed default security provider GmsCore_OpenSSL
42W/.dictionary.ap(14554): Verification of void io.grpc.internal.AbstractManagedChannelImplBuilder.<clinit>() took 144.316ms
43W/.dictionary.ap(14554): Verification of java.util.Map io.grpc.internal.AbstractManagedChannelImplBuilder.checkMapEntryTypes(java.util.Map) took 246.976ms
44W/.dictionary.ap(14554): Verification of io.grpc.NameResolver$Factory io.grpc.internal.AbstractManagedChannelImplBuilder.getNameResolverFactory() took 179.560ms
45W/.dictionary.ap(14554): Verification of io.grpc.ManagedChannelBuilder io.grpc.internal.AbstractManagedChannelImplBuilder.proxyDetector(io.grpc.ProxyDetector) took 106.727ms
46W/.dictionary.ap(14554): Verification of void io.grpc.okhttp.OkHttpChannelBuilder.<clinit>() took 699.886ms
47W/.dictionary.ap(14554): Verification of io.grpc.okhttp.OkHttpChannelBuilder io.grpc.okhttp.OkHttpChannelBuilder.enableKeepAlive(boolean) took 117.186ms
48W/.dictionary.ap(14554): Verification of void io.grpc.internal.GrpcUtil.<clinit>() took 373.276ms
49W/.dictionary.ap(14554): Verification of void io.grpc.okhttp.internal.CipherSuite.<clinit>() took 544.868ms
50W/.dictionary.ap(14554): Verification of io.grpc.internal.TransportTracer io.grpc.internal.TransportTracer$Factory.create() took 173.177ms
51W/Firestore(14554): (21.3.0) [OnlineStateTracker]: Could not reach Cloud Firestore backend. Backend didn't respond within 10 seconds
52W/Firestore(14554): 
53W/Firestore(14554): This typically indicates that your device does not have a healthy Internet connection at the moment. The client will operate in offline mode until it is able to successfully connect to the backend.
54W/.dictionary.ap(14554): Accessing hidden field Ljava/net/Socket;->impl:Ljava/net/SocketImpl; (greylist, reflection, allowed)
55W/.dictionary.ap(14554): Accessing hidden method Ldalvik/system/CloseGuard;->get()Ldalvik/system/CloseGuard; (greylist,core-platform-api, linking, allowed)
56W/.dictionary.ap(14554): Accessing hidden method Ldalvik/system/CloseGuard;->open(Ljava/lang/String;)V (greylist,core-platform-api, linking, allowed)
57W/.dictionary.ap(14554): Accessing hidden field Ljava/io/FileDescriptor;->descriptor:I (greylist, JNI, allowed)
58I/OpenGLRenderer(14554): Davey! duration=846ms; Flags=0, IntendedVsync=20548086580538, Vsync=20548186580534, OldestInputEvent=9223372036854775807, NewestInputEvent=0, HandleInputStart=20548203250538, AnimationStart=20548203353538, PerformTraversalsStart=20548204288538, DrawStart=20548204453538, SyncQueued=20548204491538, SyncStart=20548626490538, IssueDrawCommandsStart=20548656175538, SwapBuffers=20549270604538, FrameCompleted=20549355471538, DequeueBufferDuration=2284000, QueueBufferDuration=68983000, 
59I/Choreographer(14554): Skipped 41 frames!  The application may be doing too much work on its main thread.
60W/.dictionary.ap(14554): Accessing hidden method Ljava/security/spec/ECParameterSpec;->setCurveName(Ljava/lang/String;)V (greylist, reflection, allowed)
61I/.dictionary.ap(14554): Background young concurrent copying GC freed 16130(993KB) AllocSpace objects, 2(104KB) LOS objects, 26% free, 2793KB/3807KB, paused 46.366ms total 865.042ms
62W/.dictionary.ap(14554): Accessing hidden method Ldalvik/system/BlockGuard;->getThreadPolicy()Ldalvik/system/BlockGuard$Policy; (greylist,core-platform-api, linking, allowed)
63W/.dictionary.ap(14554): Accessing hidden method Ldalvik/system/BlockGuard$Policy;->onNetwork()V (greylist, linking, allowed)
64W/BiChannelGoogleApi(14554): [FirebaseAuth: ] getGoogleApiForMethod() returned Gms: com.google.firebase.auth.api.internal.zzak@25f8c60
65D/FirebaseAuth(14554): Notifying id token listeners about user ( GBhKIeO2kcS5x15VCBMeEqrSu862 ).
66W/Firestore(14554): (21.3.0) [FirestoreCallCredentials]: Failed to get token: com.google.firebase.firestore.FirebaseFirestoreException: getToken aborted due to token change.
67I/.dictionary.ap(14554): Background young concurrent copying GC freed 9851(622KB) AllocSpace objects, 4(208KB) LOS objects, 26% free, 2805KB/3807KB, paused 8.621ms total 458.693ms