.gradlew clean build 오류

.gradlew clean build를 입력하면 다음과 같이 나타나는데

무엇이 문제인 지 해결 방법을 잘 모르겠어요... 에러 로그는 다음과 같습니다.

Downloading https://services.gradle.org/distributions/gradle-5.6.4-bin.zip

Exception in thread "main" java.net.UnknownHostException: services.gradle.org

        at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:184)

        at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)

        at java.net.Socket.connect(Socket.java:589)

        at sun.security.ssl.SSLSocketImpl.connect(SSLSocketImpl.java:666)

        at sun.security.ssl.BaseSSLSocketImpl.connect(BaseSSLSocketImpl.java:173)

        at sun.net.NetworkClient.doConnect(NetworkClient.java:180)

        at sun.net.www.http.HttpClient.openServer(HttpClient.java:463)

        at sun.net.www.http.HttpClient.openServer(HttpClient.java:558)

        at sun.net.www.protocol.https.HttpsClient.<init>(HttpsClient.java:264)

        at sun.net.www.protocol.https.HttpsClient.New(HttpsClient.java:367)

        at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(AbstractDelegateHttpsURLConnection.java:191)

        at sun.net.www.protocol.http.HttpURLConnection.plainConnect0(HttpURLConnection.java:1156)

        at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:1050)

        at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:177)

        at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1564)

        at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1492)

        at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:263)

        at org.gradle.wrapper.Download.downloadInternal(Download.java:66)

        at org.gradle.wrapper.Download.download(Download.java:51)

        at org.gradle.wrapper.Install$1.call(Install.java:62)

        at org.gradle.wrapper.Install$1.call(Install.java:48)

        at org.gradle.wrapper.ExclusiveFileAccessManager.access(ExclusiveFileAccessManager.java:69)

        at org.gradle.wrapper.Install.createDist(Install.java:48)

        at org.gradle.wrapper.WrapperExecutor.execute(WrapperExecutor.java:107)

        at org.gradle.wrapper.GradleWrapperMain.main(GradleWrapperMain.java:61)