Migration service resetVersion method is not working

Hi

Following code return **"Null check operator used on a null value"** error

final_ _migrationService = locator``();
migrationService.resetVersion();

Due to this I am unable to reset Database version to 0.

Could you please help me out to reset database version. Thanks in advance.

flutter doctor -v
[√] Flutter (Channel stable, 2.5.0, on Microsoft Windows [Version 10.0.19042.1165], locale en-IN)
• Flutter version 2.5.0 at D:\flutter\flutter
• Upstream repository https://github.com/flutter/flutter.git
• Framework revision 4cc385b4b8 (7 days ago), 2021-09-07 23:01:49 -0700
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[√] Android toolchain - develop for Android devices (Android SDK version 30.0.3)
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• Platform android-30, build-tools 30.0.3
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• Java binary at: C:\Program Files\Android\Android Studio1\jre\bin\java
• Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b01)
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[√] Chrome - develop for the web
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[√] Android Studio (version 4.1)
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• Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b01)

[√] VS Code (version 1.60.1)
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[√] Connected device (3 available)
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• No issues found!

Regards
Muhammed Munees