User Activity

Checked availability with seller for an item, confirmed within Australia, delivery 3-5 days. Purchased and after 6 days no contact, no tracking. Messaged seller and they agreed to cancel order and issue a refund. After 9 days still no contact or refu...
I requested twice tracking details for a purchase I made. No contact from seller then 5 days later item is marked as posted but no tracking information uploaded. What should I do with an elusive seller who refuses to reply to this request.