If you run into this in Android Studio, you may need a gradle update.
I’ve ran into this while using Gradle v5.6.2 and Kotlin v1.3.61. I was also using the kotlin-dsl plugin for build.gradle . Apparently the kotlin-dsl plugin uses a version of kotlin determined by Gradle (my current theory anyways…I didn’t dig too deep). Once I upgraded Gradle to v6.1.1 everything was good.
This only affected Android Studio Gradle syncing. Gradle was still working fine from command line.