complain

Hi I ordered and paid for an item online from sellsa. The item has still not been delivered. I have been trying to get hold of them since the day I paid. Several emails remains unanswered. The phones goes to voicemail and they have a wattsapp line that they don't also respond to. Under shipping terms it says R95 for JHB but I was charged R210.00. I have not received the item and I am not able to get hold of them.