Could not find com.github.searchy2:CustomButton:1.9.0. ERROR

Question

My build.gradle file looks like this:

buildscript {
    repositories {
        google()
        mavenCentral()
        gradlePluginPortal()
        maven { url 'https://jitpack.io' }
        maven { url 'https://maven.google.com' }
        maven { url 'https://plugins.gradle.org/m2/' }
        jcenter() // Warning: this repository is going to shut down soon
    }
    dependencies {
        classpath "com.android.tools.build:gradle:7.0.4"
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:1.6.10"

        classpath 'com.google.gms:google-services:4.3.10'
        classpath 'gradle.plugin.com.onesignal:onesignal-gradle-plugin:[0.12.10, 0.99.99]'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

ERROR

Could not find com.github.searchy2:CustomButton:1.9.0.
Required by:
    project :app > com.github.searchy2:CustomPermissionsDialogue:2.2.1