Gradle not able to access https links for gradle-3.6.0.pom

Hi all i am new to gradle.
I am developing an android application using Qt(C++). i have upgraded my Qt from open source 5.9.0(which uses “ant”) to QT5.15.1(which uses “Gradle”) for generating APK. During building(while generating the apk) Qt is invoking gradle to generate API. But build is getting failed because gradle is not getting downloaded from provided websources internally. So i have manually downloaded the required gradle version from gradle’s official page: [https://gradle.org/next-steps/?version=5.6.4&format=all].

Downloaded ZIP file path(local path) is configured in .properties file(gradle-wrapper.properties) instead of websources (for accessing gradle offline)and build the project. QT has access to the gradel folder(located locally) but still have problems to access few of the https links(ex:https://dl.google.com/dl/android/maven2/com/android/tools/build/gradle/3.6.0/gradle-3.6.0.pom).

We sense we have to configure POM files but not sure where it should be placed locally.

For more clarity here is the screenshot while building
(check the attached file for the errors

)

I have provided environmental variable also for proxy server:"_JAVA_OPTIONS". But that also did not resolved the issue.
I have clarified with Qt team and this is not an issue with Qt tool. Somehow gradle is not able to connect to internet even after providing proxy server info.

Please help me to resolve this issue. Thanks in advance.