QuickBooks manufacturing 2014 Item list issue, using Windows 10

I have a huge item list approx. 900 items. I sorted them as per my way. During an estimate, I scroll the list & add the items. Rather than doing arrow tab with mouse, I do with the ctrl L & ctrl U to enter items. Because it’s faster for me. But now, don’t now the cause, why I can’t able to use the ctrl L and ctrl U method to arranged it. It would be very helpful If you share any idea to get it back.