When calling createNewFile() in android/java, why do I get: java.io.IOException: No such file or directory

We have tried to create a file in android by getting a path, making a new directory and then creating a file in that directory, but we get an error on runtime.
Here is the code:
<!-- language: java -->

private File createTestFile() throws IOException {
    String rootPath = Environment.getExternalStorageDirectory().getAbsolutePath() + "/RNDAlexaData/";
    Log.d("rootpath", rootPath);
    File root = new File(rootPath);
    if (!root.exists()) {
        root.mkdirs();
    }
    File f = new File(rootPath + "test.pcm");
    if (f.exists()) {
        f.delete();
    }
    f.createNewFile();
  
    FileOutputStream out = new FileOutputStream(f);

    out.flush();
    out.close();

    return f;
}

Output from android:
<!-- language: java -->

D/rootpath: /storage/emulated/0/RNDAlexaData/
D/Response error: java.io.IOException: No such file or directory
W/System.err: java.io.IOException: No such file or directory
        at java.io.UnixFileSystem.createFileExclusively0(Native Method)
        at java.io.UnixFileSystem.createFileExclusively(UnixFileSystem.java:317)
        at java.io.File.createNewFile(File.java:1008)
        at aut.rnd.alexa.ui.account.AccountFragment$TokenListener.createTestFile(AccountFragment.java:318)

Android Manifest has these permissions:
<!-- language: xml -->

<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" android:maxSdkVersion="18"/>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>

Fixed my own problem with the help of googling and @blackapps & @Andreas in the comments.

<!-- language: java -->
Environment.getExternalStorageDirectory() was deprecated, use <!-- language: java -->mContext.getExternalFilesDir(null).getAbsolutePath() instead.

private File createTestFile() throws IOException {
    File dataFolder = new File(mContext.getExternalFilesDir(null).getAbsolutePath(), "RNDAlexaData");
    Log.d("parent", dataFolder.getParent());

    if (!dataFolder.exists()) {
        Log.d("mkdir_success", "Succesfully created directory: " + dataFolder.mkdirs());
    }
    else {
        Log.d("fileexists", "true");
    }

    File testMediaFile = new File(dataFolder, "test.pcm");
    if (testMediaFile.exists()) {
        testMediaFile.delete();
    }
    Log.d("media_file", "successfully created: " + testMediaFile.createNewFile());

    FileOutputStream out = new FileOutputStream(testMediaFile);
    // TODO
    out.flush();
    out.close();

    return testMediaFile;
}