App doesn't show up in list of apps that opens up a file with a custom file extension in other apps

I have been searching for a while and found out that I could use data providers using Intent Filters to enable my app to open up a custom file extension when I try to open the file in apps like File Managers and Whatsapp. But the funny thing is that it works only when I use a File picker on my MIUI device but my app doesn't show in the list when I click to open it from Whatsapp or my in-built File manager. This is my code below, exactly everything I have tried since:

  <activity
     android:label="@string/app_name"
     android:name=".exports.ImportActivity"
     android:configChanges="orientation|keyboardHidden"
     android:exported="true"
     android:screenOrientation="portrait"
     android:theme="@style/AppTheme.SlideVertical_recipient"
     android:windowSoftInputMode="adjustResize">
     <intent-filter>
        <action android:name="android.intent.action.VIEW" />
        <category android:name="android.intent.category.DEFAULT" />
        <category android:name="android.intent.category.BROWSABLE" />

        <data android:scheme="file" />
        <data android:scheme="content" />
        <data android:host="*" />
        <data android:pathPattern=".*\\.tmly" />
        <data android:mimeType="*/*" />
     </intent-filter>
  </activity>

from App doesn't show up in list of apps that opens up a file with a custom file extension in other apps