Invariant Violation: requireNativeComponent: "BlurView" was not found in the UIManager
First check you have blur view in package.json file if not then install new one
run=>. yarn add @react-native-community/blur
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There are two main thing which cause this error
1. you have added the blur view but have not installed the pods
run=> cd ios && pod install && cd ..
2. the 2nd cause is you did pod install but did not rebuild the app
========you stop the bundle and =====
run=> yarn ios (this will rebuild the app)
Done