The whole story of what happened to you sucks!
Same thing for me. Sent in my perfectly working FAA N-Numbered bird with a small hairline crack near motor, still on warranty. They sent back a refurb with a different serial number, so I lost my N-number which was a hassle of paperwork and money to get! Now I need to cancel the N-number with the FAA before they send out my aircraft to someone else who crashes it. What a p.i.t.a.! (also I included a letter telling them I needed the aircraft with specific serial number back fixed or not, on the initial request online, in the shipping box, and taped to the body of the drone. Obviously nobody read that!)
DJI sucks, I was thinking of buying an
Inspire2 but have second thoughts now as that is a lot of money to invest into a company that does not care about it's customer.
Now I think I will use this refurb until it too cracks or has some unknown problem, then give up my 107 and find something else to do with my time. Looks like our idiot congress will pass some bad drone laws allowing stupid cities and states to make up all kinds of new rules that are different from one town to the next, making it impossible to fly or do business anyhow.