National Covers review: Boat tarp 16x20

I ordered the boat tarp on November 18th 2024. I paid using PayPal. I was informed that the cover was on backorder and would ship December 12th. I was not pleased but agreed to continue with the oder. After the December 12th date passed I emailed and asked for an update. I did not receive a reply so I called. I was told it was received and would be shipping in a few days. Nothing received. I emailed again and then again. The 3rd time I emailed I was told the cover would not ship until after the first of January 2025. I could not wait that long. I was asked if I wanted to cancel the order via an email. I said yes please. This was December 21st on the 23rd I emailed again because nothing had happened. I emailed 3 further times requesting a full refund. Nothing happened until today January 3rd. I received a cover via UPS. After I received the cover I called and spoke to customer service. They were no help. Then I received an email with shipping information and it said it was delivered after stating it was shipping. This was after I cancelled the order 3 times and called once. Now they want me to pay to ship the cover back. I ordered a cover from another company on December 22nd. I received it December 24th. Unbelievable I know. Anyway I just want a full refund and I don't believe I should have to pay for shipping and take a 18 percent restocking fee because I cancelled the order long before it shipped and it was not a custom made order. Please help me resolve this and get my refund.