Worst service and *****ing from clients

I ordered a product and paid for it. Since then I have been getting reminders to make payment and my order was even canceled. I tried logging the problem or getting hold of someone to sort this out, but nothing. Instead I get another reminder to pay. If they bother to contact me I can provide them with the proof of payment and confirmation email.

Now my order is getting delayed even more each day because they don't bother calling me back.

I just want my money back, I don't need their poor service ever again.