First, comment that the packaging line in the pubspec. yaml file and run flutter pub get after successfully get packages to uncomment that line (if you want to upgrade/downgrade to a specific version that mentioned version too) it will upgrade to the latest version.
Read moreHow do you get the Flutter packages?
From the terminal: Run flutter pub get . From Android Studio/IntelliJ: Click Packages get in the action ribbon at the top of pubspec. yaml . From VS Code: Click Get Packages located in right side of the action ribbon at the top of pubspec.
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