Updates fail to install

I am using Photoshop Elements 13 on a Mac Pro 10.13.6 and each time I open the app. I get the message that there is a new update.  This has happened lots of times.  Each time I clicked on "Install upon closing" button because I have started a simple task and want to get it done.  Each time I am asked for my password and then a window oprns that says "Update Complete "and the message "The following applications were successfully updated."  However, there are no applications listed.  Each time when I open PE and check the version I still see 13.0.   A second problem is that now the PE window is too large to fit in my screen and I cannot access the resize handle in the lower right corner.  Thus I can't acces the tools at the bottom of the window.