Issues with order. Live chat failed. Support ticket closed.

Help! I purchased a laptop through dell outlet. My issue is with the amount I was charged compared to the order receipt. The laptop as I saw it on the outlet was $632.61, and is reflected correctly on the receipt. The sub total is somehow $682.00 without any other prices shown. The total that I was billed was $729.74, for a single item valued at $632.61 (laptop) + $47.74 (7% tax of $682.00) + $49.39 (unlisted). To add insult to injury, I used live chat support to try to figure out where the anomalous value was added, and was then given nonsensical answers for 30 minutes until the agent closed the chat on me. It doesn't stop there though, because I opened a support ticket via email, and had it abruptly closed for reason: "Customer initiated phone contact." I never called. I wasn't even on my phone. So... Anyone want to help explain to me why these numbers aren't adding up, or direct me to someone who can?