Kdiizle

Hi there, I've purchased 4 t-shirts from a small Australian company however I have only received 2 of the items. On top of this, I have been charged customs duty, import VAT and clearance fee. How do I go about receiving a refund on these? My understanding is to request a refund with the Australian company once they have received the items back and then I can create a claim with Parcel Force? - what information should I provide parcel force? Thank you!