No Multi-Window/Split-Screen mode on Galaxy S6?

A

AC Question

I recently purchased a Galaxy S6 about a month ago, and was very pleased with the multi-window/split-screen function on the device. However, today I noticed that, for some reason, I could not access the function. I do not know how long this function has been missing.

Long-pressing the app switcher button does not do anything. Opening the app switcher shows that apps which normally should and did have the double rectangle icon (representing that the app is capable of being multi-tasked) do not have the symbol.

I searched for hours on Google for a solution to this problem, but I could not find anything. In fact, I seem to be the only one having this problem.

Most sites mentioned a Multi-Tasking tab in Settings, under Device, but that tab is absent from my Settings completely.

What happened? What can I do to reenable the function?