[SOLVED] When running my android studio app on my phone, it runs but does not save it on my phone

When running my android studio app on my phone, it runs but does not save it on my phone

I have previously ran projects and they not only run but save as apps that I can open again later. Now for some reason this particular projects runs and opens but does not save as an app on my phone.

I'm sure I must be missing some simple setting but I can't find any solutions, any help would be appreciated.

Thanks

edit: I am using a Samsung s10 5g, I am coding in Kotlin, I didn't think these things were relevant because I can run my other projects which were also coded in Kotlin and those will save as normal apps on my phone.

<?xml version="1.0" encoding="utf-8"?>

<application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
    <activity
            android:name=".Pythagorean">
    </activity>
    <activity
            android:screenOrientation="portrait"
            android:name=".MainActivity">
        <intent-filter>
            <action android:name="android.intent.action.MAIN">
            </action>
        </intent-filter>
    </activity>
</application>

Solution

Go to Settings -> apps -> (find the application by name) -> uninstall for all users (Depends upon the device you are using)

Then run your app again via Android Studio in your phone. Check if it helps.

<application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
    <activity
            android:name=".Pythagorean">
    </activity>
    <activity
            android:screenOrientation="portrait"
            android:name=".MainActivity">
        <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
    </activity>
</application>