What will happen to the people who disregarded all the prophets' miracles as magic?

We know that many prophets performed miracles and many people didn't believe these prophets because they thought it was all magic. But will Allah punish these people? Why would Allah punish them in the afterlife? In the Quran, Allah says that he will not charge a soul beyond it's capability. So if a person is not capable of distinguishing between miracle and magic, why should Allah punish him? It just means that Allah needs to show a stronger sign.