IMEI differs to the one I registered

This is going to sound very strange and I'm wondering what could have led to this. I received my iphone 14 pro last October and immediately registered it for insurance purposes with the IMEI number. I am the only person in my household with an iphone 14 pro. When I enter the IMEI number it automatically populates with the phone make and model - iphone 14 pro. Simple.

My phone was stolen this weekend so I logged it and need proof of purchase, barring...etc. I contact my provider and they send this but it is for a different IMEI number. I contact them and they confirm they sent me an iphone with IMEI #2 (which differs entirely from the one I have) and that has been used with my phone number until September 16th, when it was barred.

I don't have the box, I don't have anything to prove that the IMEI entered was on the phone but I don't have any other iphone 14 pro and I don't see how I could make up a number and just so happen to also get an iphone 14 pro IMEI number that's valid.

Obviously my insurer is only insuring the IMEI #1 that I shared but I don't have access to this phone (apparently I never have).

Is it ever possible to have 2 IMEI numbers?! OR that the packaging refers to a different IMEI number?!

Thanks for any insight, feel like this is going to be a lot cause though. So glad I paid for that insurance every month!