@Algis16 I'm a bit confused by your bank's choice of terms, as you can certainly own your property (and presumably your bank already has proof of this) but one can't "own" an Airbnb in the conventional sense, because it's not a tangible object. It's just a listing on a platform that is not owned by you. You wouldn't say, if you sold a table on Craiglist, that you "own a Craigslist," right?
If what your bank wants is proof of the ongoing income you've been deriving from the Airbnb rentals, you can generate a CSV from your Transaction History .