What are you trying to achieve: make the object face its movement direction, toggle its direction, or flip its collision shape?
Get Graphic Flip only reads the graphic’s current X and Y orientation. It does not change anything. Connect your event to Get Graphic Flip, pass the Flip X or Flip Y output into an If, then connect the matching Set Graphic Flip behavior after the If. Make sure both behaviors target the same object.
One important detail: Set Graphic Flip changes only the artwork, not the collision shape. If the collision body must turn too, use Scale To and set the relevant scale to a negative value.
Could you share a screenshot of your behavior chain and describe the result you want? That will make it easier to show the exact connections.