If the person that is panicking does not listen to what you are telling them, it isn’t because they don’t care. They aren’t listening because they are PANICKING. In their mind everything is going 1000 miles per second and they are thinking of the worse case scenarios for everything. They are trying to breathe, trying not to self harm, or trying to focus on thinking somewhat straight.
So stop thinking that they don’t care about you or they are mad at you. Don’t storm off and get angry if the person who is panicking doesn’t respond the way you want them to. Don’t yell at them! Be calm and just sit with them.
They want to control themselves just as much as you want to control them.