Do this in your projects app level build.gradle
configurations.all { resolutionStrategy.eachDependency { DependencyResolveDetails details -> def requested = details.requested if (requested.group == 'com.android.support') { if (!requested.name.startsWith("multidex")) { details.useVersion '28.0.0' } } } }

Add this to the very end of your build.gradle (Module:app):
configurations.all { resolutionStrategy.eachDependency { DependencyResolveDetails details -> def requested = details.requested if (requested.group == 'com.android.support') { if (!requested.name.startsWith("multidex")) { details.useVersion '25.3.1' } }
} } Make sure that you replace '25.3.1' with the version of the android support library that you want to use for all the dependencies , it should not be lower than your complile sdk version
than re sync gradle