An OAuth2 client already exists for this package name and SHA-1 in another project
<p>I was practicing <code>firebase</code> CodeLab <a href="https://codelabs.developers.google.com/codelabs/firebase-android/#0" rel="noreferrer">(Friendly Chat)</a> for learning <code>firebase</code> with <code>android</code>. In that tutorials ,I made a project on firebase console named as "<code>Friendly Chat</code>" and then I add my android app <code>package name</code>  and <code>SHA-1</code> so that invites and Google Auth could be work. After that tutorial get compeleted, I got firebase <a href="https://firebase.google.com/docs/samples/#android" rel="noreferrer">Auth demo project</a> from github.I add auth demo project's <code>package name</code> and <code>SHA-1</code> in same console project "<code>Friendly Chat</code>",its mean now console project "<code>Friendly Chat</code>" have two <code>android</code> apps.Then I downlaoded <code>google.services.json</code> file of Auth project and when I run project in <code>Android Studio</code>,Auth demo did not work as it keep showing <code>loading progress Dialog</code>.I thought it may be because I added two <code>android</code> apps in same console project so,I delete auth app from <code>Friendly Chat</code> console project and made another project on firebase console named as "<code>Project Auth</code>" and I add package name of Auth demo android project (which I downloaded from firebase github repository) but when I tried to add SHA-1 copied from "Friendly Chat" console project,it gives me below error</p>

<p>"An OAuth2 client already exists for this package name and SHA-1 in another project"</p>

<p>why Im getting this error even I have deleted Auth app package name and SHA-1 from other console project.</p>