"Today, I went to the resolution center and it said that the case was closed yesterday and I can not file a complaint about it as of today."
Deadline is 45 days from time of purchase to file a complaint with the Resolution Centre. Unfortunately, you missed the deadline.
http://pages.ebay.ca/help/buy/resolving-problems.html
If you paid with a credit card through PayPal, you can contact your credit card issuer (bank) and ask for a chargeback for goods not received.
I find it surprising that you placed two orders with the same seller (feedback rating over 95,000) on May 3rd and May 4th, received one item quickly and left positive feedback while the other one never arrived and they never replied to your inquiries.
Good Luck.