Lack of communication and missing product

I recently made a purchase and noticed that one of the items I had ordered was missing when I received my order. Additionally, I discovered that the invoice amount was different from the amount I had been charged at checkout, on the invoice I was sent it shows as if I didn’t purchase the product but on the checkout invoice the product it there. I reached out to via email with my concerns and have yet to receive a response. I am disappointed in their lack of communication and attention to detail.