According to the Inheritance Law, a testator can revoke or change his will. If there are several wills made, and the contents conflict with each other, the last one shall prevail.
That is, if the testator has made multiple wills (except notarial wills), and the contents of the wills conflict with each other, the contents of the last will shall prevail.
However, if there is a notarized will in multiple wills, the notarized will shall prevail, and the effect of notarized will is higher than that of other wills. Except for notarial wills, self written wills, proxy wills, audio wills and oral wills have the same effect.
