It appeared a long time ago, and no one knows the prototype and the user carefully, only that it appeared

The timeline of this book begins: the protagonist is reborn---> the protagonist obtains the Law of Time (non-public), ----> is entrusted by Zhu Yue (semi-threatening) --->to travel back in time to save Zhu Yue (he used the Law of Time in front of the jewel and was recognized, so it is included in the record of the Magicians Association) ---> return to the present (because the protagonist travels directly through time, so it is natural that no one has been able to find him all these years)

Probably this feeling, the principle is based on the theory of reverse cause and effect that I don't know about a certain book