open apps are not appearing in taskbar

I am rnning music and the app first appears when I play a file but does not appear in the task. Here is a screenshot.



In order to get to the app, I have to do the thing where you bring your finger in from the left and it opens the most recent program, then I have to minimize it, then I have to click on the desktop icon to get back to the desktop, and then it appears.



Why doesn't it appear when I open it?