SwiftXpress – Delivery service

I made an online purchase from what I thought was a credible company’s website only to find out that they are in cahoots with a shipping company called swiftXpress. After I placed my order from the company I got an email from SwiftXpress indicating my package cannot be shipped unless I paid the refundable upon delivery $300 security deposit. After four days I’m not receiving my package I inquired to the shipping company about the delay and They told me I needed to pay another $400 for some BS FDA insurance. At that point I immediately knew it was a scam. Unfortunately they got me for the $300 and the other company got me for $500. Please learn from my mistake.