Get Image File from public folder in backend

I'm trying to get an image from the public folder but I'm having issues where it always returns null.

This is my full code

 $filename = $id . '.png';
$fileDirectory = public_path('reportImages');
$fullFilepath = public_path('reportImages') . '/' . $filename;

			//create image
            $image = imagecreate(300, 200);

            $black = imagecolorallocate($image, 0, 0, 0);
            imagecolortransparent($image, $black);

            $red = imagecolorallocate($image, 255, 0, 0);

            imagerectangle($image, 5, 10, 195, 50, $red);

            File::ensureDirectoryExists($fileDirectory);

            imagepng($image, $fullFilepath);

            imagedestroy($image);

if I add dd(Storage::disk('public')->get('/reportImages/e96b4467-055d-4e5a-8c4e-bf2af6261177.png')) which is the real file name it returns null.

The full path for the file is /home/programador/code/btl-visor-new/public/reportImages/e96b4467-055d-4e5a-8c4e-bf2af6261177.png

What am I doing wrong? I'm trying to get the file to obtain the width and height of the image and finally I want to merge two images together.