Android requestpermissions does not display a dialog box

I found many similar topics, but they all faced the same threat, but I still couldn't find a solution to my problem. I wrote this code to grant write permission to the application, but there was no dialog box. I entered the monitor and saw the message that I didn't have write permission

if(ContextCompat.checkSelfPermission(getContext(),Manifest.permission.WRITE_EXTERNAL_STORAGE)!= PackageManager.PERMISSION_GRANTED) {
Log.i("permissions", "No writing permission");

ActivityCompat.requestPermissions(getActivity(), new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, 225);

I added permissions to the androidmanifest file

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

The target SDK targetsdkversion 23 has been changed, and I am using Android 6.0.1

Edit: I also bound this code, but it still doesn't work properly

requestPermissions(new String[]{android.Manifest.permission.WRITE_EXTERNAL_STORAGE}, 225);

resolvent:

The requestpermissions dialog box is displayed on > = 6.0 devices only in the following two cases:

1) You have granted permission for any hazard permit in the category you requested

2) When the dialog box was previously displayed, you clicked the do not ask again check box