website gone after i purchased goods online

i purchased a Kitchen Aid mixer from the website www.kavios.com and i could trace the package till last week and it was at customs at that time. Now i cannot make contact with this website to follow up and the package was purchased and paid for in November already.

What can i do?

I also purchased stuff from wish.com which was delayed and when i followed up, they told me they cannot refund me as i waited to long and i also haven't received the items.

i please need to know what i can do please