New Mazda transmission doesn't fit..any clues why?

We have a 2015 cx5. We had to order a new transmission and so we ordered it using the VIN number. When it arrived it didn’t fit. Verified the VIN number, model and make. Mazda said that this particular car has an odd transmission that requires a different siZe not associated with the VIN. Anyone else had this issue before? Can’t find much on it online

Is it a problem to return the wrong-size transmission and exchange it for the correct size?

Well the dealership said the correct transmission size is apparently hard to find and almost double the total price

Just seemed odd the VIN didn’t line up with the correct model

That’s a bummer. I guess 2020 isn’t starting out on the right foot for you. Sorry to hear you are having this difficulty, very frustrating. Unfortunately I have no information for this specific situation so can’t be of much help. I guess if I had this problem and a visit to the local Mazda dealership didn’t offer up anything of value I’d try some internet Mazda forums, and probably purchase some Mazda-performance related magazines, and phone up some of the advertisers who appear like they’d know something about Mazda transmission issues. The performance experts tend to know about ways to work around problems like this. But be prepared, you may find yourself in the “round peg wont fit in a square hole” situation, and you have no other option than to somehow find & purchase the other transmission.