Delta charizard don´t envolve

my charizard not mega evolves despite already got the stone, the funny thing is that the stone in the battle goes with symbol “X” but says delta charizardite bag and my Pokemon does not evolve

Z or ⇧ Shift keys are the default for both running and mega evolution. If they don’t work, you probably have rebinded your keys in the Controls.

What do you mean by that? Could you screenshot it?

It won’t work if the stone is in your bag, your charizard needs to be holding it as an item.