A can is stuck in a drink machine.

Shalom Rabbi!
A. If you ask the company that owns the cans, they will tell you not to touch the machine and not to do anything until I arrive, and that will take time, and in such a situation, what is the ruling, even though they say no, will it be permissible? And from what ruling?

In principle, one should follow their instructions, but of course demand the money back. There is room to deviate from this formalism in a place where it is completely clear that no harm will be caused to the machine and the company (one is responsible for oneself). I don't know how well you can know such a thing.

And regarding the firstborn, how can you sell firstborn winnings if the 4th is not the firstborn? Oh, come on, Talia.

Regarding the birthright, it is not true. Let's say I inherit some money from my father. And now I sell it to someone else. And can I not sell (I am not talking about issues of appropriateness and something that never comes into being and something that is not specific, but in principle)? Of course I can. As long as I am the owner, and it does not matter who owns it by what power, I can sell.
The Gemara in Matot 5:1 speaks of a woman who sells her right of access to a ketubah. The buyer acquires her rights in the ketubah if and when they come to her. The buyer is not married to the woman's husband and the rights of the ketubah are granted to the woman by virtue of her marriage. Nevertheless, the rights granted to the wife of that husband can be sold to him.

And the law does not belong here, it is enjoyed and it is not lacking (the owner of the machine)

A zanuzel is an exemption from payment for using someone else's property. This is not about that, but about taking legal action for oneself. It is clear that the relevant fact is that the owner of the machine will not suffer any damage (that there will be no shortage), as I wrote.

Shalom Rabbi!
In the topic we discussed a long time ago about the can machine, you wrote that if no damage is caused to the machine, it will be permissible according to the law of the worker who is not responsible for his own life. The whole point of the issue of the worker who is not responsible for his own life is when he stole from his hand, and then there is a distinction between a place of loss or a loss of money. But here in the can machine, it is clear that if you tell him about the can, he will tell you to wait for me until I arrive and there is no theft here. That is how I understand the Gemara, and that is how the head understood it.

I speak when it is clear to you that no harm will be done. In such a situation, there is no need for special permits.