If you are using react-link to link your dependencies:
0pen your ios Podfile and delete all yout linked dependencies: pod 'xxxxxxx', :path => '../node_modules/xxxxx
Close Xcode
In your /ios folder run "pod update"
In your project source run "react-native link"
Open Xcode and Clean Build Folder from Xcode Menu -> Product
Run your application from Xcode
Link manually the dependency "react-native-gesture-handler" into your Xcode Project following steps in documentation: https://facebook.github.io/react-native/docs/linking-libraries-ios
Now run your application from Xcode, you should be fine.