For a NativeScript app, this error usually occurs in the context of iOS app development, specifically when you or some of plugins you installed, are trying to use background tasks.

To fix this problem
- Open your app’s App_Resources/iOS/Info.plist file.
- Add the key BGTaskSchedulerPermittedIdentifiers if it’s not already present.
- Set its type to Array.
- For each background task, add an item to this array. Each item should be a String representing a unique identifier for a background task.
Example usage:
<key>BGTaskSchedulerPermittedIdentifiers</key>
<array>
<string>$(PRODUCT_BUNDLE_IDENTIFIER)</string>
</array>
If you have any custom background task, you will need to list its id in above array also. Other than that, you can use above piece of code as it is.
PRODUCT_BUNDLE_IDENTIFIER, will be resolved to your app Bundle id defined in nativescript.config.ts, something such as: com.newbiescripter.myawesomeapp
Remember that using background tasks in iOS comes with certain restrictions and guidelines, as Apple aims to optimize battery life and performance. Make sure your usage of background tasks aligns with these guidelines.
Happy coding ❤️.