Could not resolve all files for configuration ':app:debugRuntimeClasspath' - flutter

Question

I am trying to build the flutter application. It was working fine before but suddenly this error is being shown:
Execution failed for task ':app:checkDebugAarMetadata'.
> Could not resolve all files for configuration ':app:debugRuntimeClasspath'.
> Could not resolve com.github.yalantis:ucrop:2.2.6.
Required by:
project :app > project :image_cropper
> Could not resolve com.github.yalantis:ucrop:2.2.6.
> Could not get resource 'https://www.jitpack.io/com/github/yalantis/ucrop/2.2.6/ucrop-2.2.6.pom'.
> Could not HEAD 'https://www.jitpack.io/com/github/yalantis/ucrop/2.2.6/ucrop-2.2.6.pom'.
> Connect to www.jitpack.io:443 [www.jitpack.io/149.56.28.39] failed: Read timed out
Following is my build.gradle file:
buildscript {
ext.kotlin_version = '1.3.50'
repositories {
google()
jcenter()
maven { url 'https://www.jitpack.io' }
mavenLocal()
maven {
// All of React Native (JS, Obj-C sources, Android binaries) is installed from npm
url("$rootDir/../node_modules/react-native/android")
}
maven {
// Android JSC is installed from npm
url("$rootDir/../node_modules/jsc-android/dist")
}
}
dependencies {
classpath 'com.android.tools.build:gradle:4.1.0'
classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
}
}
allprojects {
repositories {
google()
jcenter()
}
}
rootProject.buildDir = '../build'
subprojects {
project.buildDir = "${rootProject.buildDir}/${project.name}"
}
subprojects {
project.evaluationDependsOn(':app')
}
task clean(type: Delete) {
delete rootProject.buildDir
}
I tried all the answers specified in github and stackoverflow. none of them worked. Please help me