Collision animation help needed

In the file I have attached, if you move the red box toward the blue bar using the up arrow key, the first time the red box collides with the blue bar, the animation plays. But each time after that, when the red box collides with the blue bar, the animation does not play. Can you please help me so that the animation plays each time there is a collision. Thank you.
collision-test.zip (2.97 KB)

Like this?

collision-test.gdg (27.2 KB)

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For easy testing, choose the web platform to restrain the extentions, but test with Windows, so you can use the debugger and stuff.

Thank you for your help. This was what I needed. Merci.