Why did Zhu Yuanzhang's gold medal from death expire?

Since ancient times, the founding emperor likes to give heroes a gold medal to avoid death. After all, it's just a psychological comfort. Few emperors really don't kill heroes. After Liu Bowen got Zhu Yuanzhang's gold medal for avoiding death, Liu Bowen didn't watch it, because he felt that he was different from other heroes, and he wouldn't be the object allowed by Zhu Yuanzhang. So when he retired and was secretly watched by Zhu Yuanzhang, he realized that he would not be spared by Zhu Yuanzhang, so he remembered that he still had a gold medal to avoid death. Who would have thought?

Liu Bowen is the hero of Zhu Yuanzhang's creation of Daming Mountain. He is different from other heroes. He is not a military commander and has no military power. Moreover, he did not hold an important position in the country after the establishment of Daming Jiangshan, so he would not be a hero suspected by Zhu Yuanzhang. However, Liu Bowen didn't figure it out. He was a fortuneteller. Although he is a counselor, he likes to study astronomy and geography, so he often predicts the future like a god and always comes true.

In that particularly superstitious era in ancient times, Liu Bowen just painted himself with a layer of myth, which seemed nothing, but Zhu Yuanzhang was born in the peasant class and was superstitious. When he fought for his country, people like Liu Bowen helped themselves by telling the world that I, Zhu Yuanzhang, was a chosen son. This is a foregone conclusion. This Liu Bowen is an imperial time bomb.

If one day Liu Bowen and Zhu Yuanzhang leave Germany, and he makes any predictions, will Zhu Yuanzhang's country perish in II? So Zhu Yuanzhang can't hold this Liu Bowen, so the death-free token that Zhu Yuanzhang gave Liu Bowen at the beginning will have a time limit.