I purchased my mavic on amazon from linked all drones. It was delivered yesterday and I was unable to open it until this morning. I just opened the mavic box and I see that I have two props installed on the rear legs, no props installed on the front legs. I see the molded case is molded for props on the top of the drone. So I opened the fly more box. Inside I have a set of white marked props and a set of unmarked props. In total, I have six individual props. Before I start sending out emails, is this correct? Now I'm concerned I got a refurbbed unit myself since I think the props are missing and there was a large blob of black sticky stuff on a rear leg that I had to scrape off with a fingernail. Where is the serial number located so I can check?