Sorry, there's just no way you can successfully touch up or repair powder coat - that's precisely why I refuse to use it for anything. I'd send it back.

Rich

Yup.
Faux finish touch up is the only onsite solution.

Clear powder coat is very finicky.
I have had rust fingerprints magically appear 2 or 3 months after a piece was clear powdercoated. Silver pencil, sharpie, and even regular pencil can suddenly be very noticeable, UNDER the finish, as well.
Had a chair that was clear powdercoated peel like a bad sunburn, with tons of rust under the finish, after about 1 year on a back porch in downtown San Francisco- under cover, not in the rain, just from the salt air.

I used to do a lot of powder coating for indoor products, but I never warrantee it for any outdoor piece, and always recommend against it outdoors.
Powder is pretty tough, but once rust starts underneath it, its over.

And even getting it stripped and refinished is a bear. If your coater doesnt have a burnout oven, big enough to bake the whole piece at 1200 to 1500 degrees, then sandblasting alone is the only alternative, and that often doesnt work very well.

For any paint finish, you need to be able to recoat. Powder is a one shot, disposable finish for our disposable world, but its a lousy finish for high quality stuff you want to last 50 years or more.

aloha,ron