That fork crown race doesn't look right to me.
The eBay special FSA headset should have come with all the parts, including the crown race.
With older style loose ball bearing headsets you can sometimes get away with using a different crown race, but with these sealed bearings the diameter and angle of the race/bearing carrier has to be correct or you'll have problems.
I know it's a bit of work, but I'd take it all apart & confirm you've got all the correct parts in the right order.
If you're missing the crown race then get onto the eBay seller about it.
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