I can no longer select multiple objects by dragging a square around them

I can no longer select multiple objects/items in a PDF I am trying to edit by dragging a square around them. I’ve searched the help and it appears this issue has been going on for years, but this is a new issue for me. I am using Adobe Pro and it is work licence and I have the latest Windows operating system and Adobe updates. I have always been able to select multiple items and now I cannot. Has anyone found a way to get around this. Adobe can you fix? I will have to use another application.