react-native :app:installDebug FAILED

Since you are using Mi phone which has MIUI

try this

go to Developer options, scroll down to find 'Turn on MIUI optimization' & disable it. Your Phone will be rebooted

check now

If you are using any other android phone, which has a custom skin/UI on top of android OS, then try disabling the optimization provided by that UI and check.
(usually you can find that in 'Developer options')

In my case, I have set up a new app but I was getting errors, tried many possible ways and answers from github and stackoverflow. nothing worked

error The solution for me was .. check if you already have an app with the same name is installed in android..

Delete old apps and run react-native run-android

Worked for me.