There is maybe some setting on program update...It probably meant for you to go to the App Store. Sometimes, when you're on the web, a new page will open temporarily, then it [somehow] calls to open the App Store. It's like magic!
Except when the "call" doesn't work - which is what I suspect happened here in this case...
Easy enough - just look the app up in the App Store.
Hope this clarifies things a bit.
Marilyn