UnityでAndroidのaabビルドをするとFAILURE: Build failed with an exception.がでてきた

unityでandroidのaabビルドをしようとするとFAILURE: Build failed with an exception.というエラーが出てしまいました。

FAILURE: Build failed with an exception.

* What went wrong:
A problem occurred configuring project ':launcher'.
> Could not resolve all artifacts for configuration ':launcher:classpath'.
   > Could not find com.android.tools.build:gradle:6.2.0.
     Searched in the following locations:
       - https://dl.google.com/dl/android/maven2/com/android/tools/build/gradle/6.2.0/gradle-6.2.0.pom
       - https://dl.google.com/dl/android/maven2/com/android/tools/build/gradle/6.2.0/gradle-6.2.0.jar
       - https://jcenter.bintray.com/com/android/tools/build/gradle/6.2.0/gradle-6.2.0.pom
       - https://jcenter.bintray.com/com/android/tools/build/gradle/6.2.0/gradle-6.2.0.jar
     Required by:
         project :launcher
   > Could not find com.android.tools.build:gradle:6.2.0.
     Searched in the following locations:
       - https://dl.google.com/dl/android/maven2/com/android/tools/build/gradle/6.2.0/gradle-6.2.0.pom
       - https://dl.google.com/dl/android/maven2/com/android/tools/build/gradle/6.2.0/gradle-6.2.0.jar
       - https://jcenter.bintray.com/com/android/tools/build/gradle/6.2.0/gradle-6.2.0.pom
       - https://jcenter.bintray.com/com/android/tools/build/gradle/6.2.0/gradle-6.2.0.jar
     Required by:
         project :launcher

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 3s
Picked up JAVA_TOOL_OPTIONS: -Dfile.encoding=UTF-8

UnityEngine.GUIUtility:ProcessEvent (int,intptr,bool&)

もう一つ出てきました。

Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 3s
Picked up JAVA_TOOL_OPTIONS: -Dfile.encoding=UTF-8
]
stdout[

]
exit code: 1

#環境

Windows10
Unity 2020.3.11f1
Android SDK APIlevel 30
Android NDK r19
Android JDK OpenJDK Unity2021.1.21f1についてくるものを使ってます。
Gradle 5.6.4

#試したこと

Player Settings＞Publishing Settings＞Build＞Custom Main Gradle TemplateとCustom Launcher Templateを有効にし、

buildscript {
    repositories {
        google()
        jcenter()
    }
    dependencies {
        //                                         ↓Gradleのバージョンを指定しました。
        classpath 'com.android.tools.build:gradle:5.6.4'
    }
}

を追記しました。