Animation sequence won't start

I've been using this tutorial (https://youtu.be/A9dz0uHu_20) to set up an engine for a game I'd like to make. However, around the 15 minute mark, I had some difficulty with getting my walking animation sequence to start. I did as instructed in the video, but the active object stays in the stopped sequence. I'm not sure what I could be doing wrong here. Thank you for any help

Pay careful attention to the event that sets the animation to idle, it's likely overriding the walk animation. You really need to screen grab your events so we can see where things are going wrong.

Attachment 24763
Attachment 24764

Sorry i didnt do that before, but here's what i have for the animation parts so far

This version is good working. Hope to see the next one

The problem is that even though this is supposed to work, no animations start..

Actually, it's funny but a common error in your events... the problem is not that the walk animation is not starting, it's that it's RESTARTING every tick.
You need:
If character is on ground AND Character is moving AND current animation is NOT walking, THEN set the animation to walking.

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Is this what you meant? If it was then the animation still doesn't start

Since we have no clue what's behind the Green check marks, it's helpful to post the MFA
I see nowhere in your events something about moving the animation.
All you have it i's NOT playing..

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Here's my file

Ha ha ha ! Not laughing at you, just the situation. Your problem is the group you created for Animation is TURNED OFF!!! That's why the title is grey. You need to make it an active group.
Right click, choose "Edit the actions", and then make sure it's set to be active when frame starts.