An operation fails with the exception "not available for this user".
Your device was blocked. If it was set up as a test device, please let us know and we will try to fix it. Otherwise, uninstall the app which contains the SDK (make sure that its data is also removed from any automatic backups), reset your GAID (go to Settings > Google > Ads and tap on Reset Ad-ID) and set up your device as a test device with the new GAID (see above for instructions on how to do that).
You have seen the message about receiving a reward but the SDK doesn't show the new rewards.
This usually happens when the device time is incorrect. Make sure that it is correct and not maybe one day in the future or in the past. If this is not the case, please contact us with the information mentioned above and we will investigate this issue.
The app doesn't compile with the exception "Duplicate class" or "Duplicate entry".
This can happen when Gradle cannot resolve a dependency conflict, for example when two dependencies use the same transitive dependency, but with different versions. To resolve this conflict you must remove one of the dependencies or adjust the versions so that they are equal. If the affected dependency is one of your app's dependencies, you can just delete it from the dependencies list in your build.gradle or change the version there. If the affected dependency is a transitive dependency, you must exclude it from the dependency which specifies it as a transitive dependency.
Duplicate class due to androidx.work:work-runtime:$workVersion.
Our SDK supports pre-AndroidX projects and so we are using the work-runtime library that predates AndroidX. There is an issue with the Android Gradle plugin <3.6.0 where the Jetifier does not correctly replace the dependency. If you are not already using a supported version of Gradle, you need to bump the version in your root project's build.gradle file.
classpath 'com.android.tools.build:gradle:3.6.0'// Set this to 3.6.0 or higher.
// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
Please also ensure that you have enabled the Jetifier by placing the line android.enableJetifier=true into your gradle.properties file.
If you continue to have issues due to a conflict between the versions of the androidx.work:work-runtime library in your project, you can fix this issue by adding the following to your app level build.gradle file.
// Substitute one module dependency for another
substitute module('android.arch.work:work-runtime:1.0.1') with module('androidx.work:work-runtime:2.0.1')