Type mismatch: inferred type is String? but String was expected (Android)

[iliyass-zamouri]

Launching lib/main.dart on Android SDK built for x86 in debug mode...
lib/main.dart:1
e: /Users/mac/development/flutter/.pub-cache/hosted/pub.dartlang.org/facebook_event-0.0.6/android/src/main/kotlin/com/faisal/flutter/facebook_event/FacebookEventPlugin.kt: (244, 31): Type mismatch: inferred type is String? but String was expected
e: /Users/mac/development/flutter/.pub-cache/hosted/pub.dartlang.org/facebook_event-0.0.6/android/src/main/kotlin/com/faisal/flutter/facebook_event/FacebookEventPlugin.kt: (246, 31): Type mismatch: inferred type is String? but String was expected

FAILURE: Build failed with an exception.

• What went wrong:
  Execution failed for task ':facebook_event:compileDebugKotlin'.

Compilation error. See log for more details

• Try:
  Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

• Get more help at https://help.gradle.org

BUILD FAILED in 1m 19s

[vantutrieu97]

let try using ! after your string value

[AliPunjabi]

any solution?