Crash on iOS, Fatal error: Unexpectedly found nil while unwrapping an Optional value

[jjvillavicencio]

Fatal error: Unexpectedly found nil while unwrapping an Optional value: file /Users/developer/.pub-cache/hosted/pub.dartlang.org/flutter_string_encryption-0.3.1/ios/Classes/SwiftFlutterStringEncryptionPlugin.swift, line 130
2020-02-26 18:54:08.214319-0500 Runner[26699:4980971] Fatal error: Unexpectedly found nil while unwrapping an Optional value: file /Users/developer/.pub-cache/hosted/pub.dartlang.org/flutter_string_encryption-0.3.1/ios/Classes/SwiftFlutterStringEncryptionPlugin.swift, line 130