Registration office Doof?

Moin, I signed off my 318i today and registered my 330Xi E46. Ging told me she typed nicely and now I notice that I’m driving one. E46 Built 1986 xD Especially because the only 98 were built 😛 Kw 65 ????????????? 318i A chassis number that doesn’t match my old or my new xD. What I wanted to register my 330 wasn’t any misch mash from 318 and any fantasies. With the old letter everything fit from 330 but I own n How can I make it clear to the registration office on Monday that they made a mistake?? That they believe me because I just spent 53€ on something that I don’t exist xD Because the old vehicle letter they collected. Do they throw the way or do they have to keep it for a certain time? mfg Simon