This issue occurs due to a development server error.
Follow some steps to resolve this issue.
Step 1:
adb kill-server adb start-server
then verify that your device / emulator is displayed on the command line or not.
adb devices
Step 2
Clean gradle compiler files, some files may be damaged.
android/gradlew clean
Step 3:
Uninstall the application from your device / emulator.
Step 4:
react-native run-android
Now the issue will be resolved :)
Yogesh rathi
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