I have one simple question for you: "what is bitcoin"? What are you offering me to buy?
I'm not offering you bitcoin, just saying that if I ever happen to sell it to you, I'll be fine with signing a piece of paper saying that I did, because you seem to be attached to invoices and seem to think that if it's signed it becomes "real".
You don't know what bitcoin is? Do you want a link to the white paper? There's s good explanation on investopedia, bitcoin.org and other sites. I also recommend Andreas Antonopoulos on youtube.
So, you are unable to define bitcoin. Just as I thought. If the invoice has 10 iPhone 13 written on it, I have no problem defining what I am selling. The same is true for everything else, from stocks/equities that have quantity written on brokerage accounts or stock certificates, to debt that has quantity written on bank accounts or banknots. But you people are making up your own definitions of bitcoin and all are different. Instead of admitting that Nakamoto invented nonsense you're acting like some clowns.