如何解决此新的Firebase Auth错误

Question

像往常一样，我正在处理我的实际项目，我想在旧活动中添加一些新内容。当我打开.java文件时，显示了一个新的错误，其中有一个我无法思考的原因。它表示无法解析FirebaseAuth符号。我检查了我的Gradle(已更新到最新版本(和代码，但找不到解决方案。如果有人能帮助我，我将不胜感激。

屏幕截图：

Gradle模块：

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'
apply plugin: 'kotlin-kapt'
apply plugin: 'com.google.gms.google-services'
android {
compileSdkVersion 30
buildToolsVersion "30.0.3"
defaultConfig {
applicationId "com.example.diligent"
minSdkVersion 19
targetSdkVersion 30
versionCode 1
versionName "1.0"
multiDexEnabled true
testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
javaCompileOptions {
annotationProcessorOptions {
arguments += [
"room.schemaLocation":"$projectDir/schemas".toString(),
"room.incremental":"true",
"room.expandProjection":"true"]
}
}
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
}
}
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_8
targetCompatibility JavaVersion.VERSION_1_8
}
}
dependencies {
implementation fileTree(dir: "libs", include: ["*.jar"])
implementation 'androidx.core:core-ktx:1.3.2'
implementation "androidx.multidex:multidex:2.0.1"
implementation 'com.google.android.gms:play-services-ads:20.0.0'
implementation 'androidx.appcompat:appcompat:1.2.0'
implementation 'com.android.support:cardview-v7:28.0.0'
implementation 'com.google.android.material:material:1.3.0'
implementation 'androidx.constraintlayout:constraintlayout:2.0.4'
implementation 'androidx.legacy:legacy-support-v4:1.0.0'
implementation 'com.github.congtung10t2:circularseekbarplus:1.0'
implementation 'com.google.firebase:firebase-auth:20.0.4'
implementation 'com.google.firebase:firebase-database:19.7.0'
}

项目：

buildscript {
repositories {
google()
mavenCentral()
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:4.1.2'
classpath 'com.google.gms:google-services:4.3.5'
classpath "com.google.gms:google-services:4.3.5"
classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:1.3.72"
// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}
}
allprojects {
repositories {
google()
jcenter()
maven {
url "https://jitpack.io"
}
}
}

Answer 1

implementation 'com.google.firebase:firebase-auth:18.0.0'
implementation 'com.google.android.gms:play-services-gcm:17.0.0'