앱 빌드 시 발생하는 오류 메시지는 무었인가요?

PS D:\flutter\ubi> flutter build appbundle

Font asset "MaterialIcons-Regular.otf" was tree-shaken, reducing it from 1645184 to 1100 bytes (99.9% reduction). Tree-shaking can be disabled by providing the --no-tree-shake-icons flag when building your app.

Running Gradle task 'bundleRelease'... 97.9s

Gradle build failed to produce an .aab file. It's likely that this file was generated under D:\flutter\ubi\build, but the tool couldn't find it.

• D:\flutter\ubi\build\app\outputs\bundle\release 에는 파일이 생성되어 있음