And there is no abnormal play? Straddle the bike on sidewalk or surface that has good tire grip. Lock the front brake and then push forward on the frame, not the handlebars, and then backwards. Does the headtube of the frame move differently than the steerer tube, spacers and other stuff? If so, you need to loosen the stems pinch bolts, then snug down the bolt going to the expanion plug or star nut and then retighten the stem bolts.
Otherwise I agree with
frankenmike It'll eventually show you exactly what the issue is. And likely not in the disastrous way you might imagine or even more expensive than anything you might do towards it now.