It’s possible that your PowerPoint presentation is not displaying the correct slide layout in slide sorter view. To try and troubleshoot the view, you can:

1. Check that your zoom level is set to 100% – if the zoom level is more or less than 100%, this can affect the layout.
2. Check that all of the slides in the presentation have the same slide layout, or that the slide layout is set to ‘blank’
3. Try running the slide layout troubleshooter, which can be found under ‘File > Info > Check for Issues’
4. In rare cases, PowerPoint can be affected by corrupt or malformed data, you can try starting PowerPoint in 'Safe Mode' to troubleshoot this. To start PowerPoint in 'Safe Mode' press CTRL + R and enter the command 'WINWORD /s'