They misunderstood you because you asked for replacement screws and missing in the same sentence.

Redo your ticket if you closed it and tell them they misunderstood and that your atomizer did not come with screws at all and that you payed for screws (defective).

Technically without screws it falls under DOA Item defective ticket or here would work to Item missing from package

FT will sort you out.

If you don't want to go the ticket route you can try find them in a local hardware or an electronics store if you want them faster.

Or hope someone knows the size so you can order them.

Good luck.