Animation not completing

My website has an animated burger icon that set to

  1. Animate into to an X and open the menu on first tap
  2. Revert back to burger icon and closes the menu on second tap

That part works fine as seen here

The nav menu items when tapped are also set to close the menu using the exact same animation set out in step two above. Which it partially does but for some reason the X does not revert back to a burger icon. Screengrab here

Any idea why this is?

Here is my public share link: LINK