no scrolling in tab 'pages' InDesign version 18.0

[warm_loyalty16B8]

I can't scroll anymore in the tab 'pages' in te latest InDesign. In 'Show pages' I tried 'vertical' , 'horizontal' as wll 'according alternative layout'. Also when I try to scroll with 'alt'. It stops at a certain pagelevel. Very irritating. Am I the only one or have I overlooked a setting? Is it a bug? Who can help me? 

[Peter Spier · Accepted solution]

Reset the preferences: Reset InDesign Preferences and Other Troubleshooting 

[warm_loyalty16B8]

Peter, thank you very much for the quick help

[Peter Spier]

You're welcome