Age of prophesy ended in Israel in the 4th century BCE. Prophesy didn't and can't exist outside of Israel. So anyone claiming to be a prophet is lying and according to Deuteronomy 13 should be executed.
1Everything I command you that you shall be careful to do it. You shall neither add to it, nor subtract from it.
2If there will arise among you a prophet, or a dreamer of a dream, and he gives you a sign or a wonder,
3and the sign or the wonder of which he spoke to you happens, [and he] says, "Let us go after other gods which you have not known, and let us worship them,"
4you shall not heed the words of that prophet, or that dreamer of a dream; for the Lord, your God, is testing you, to know whether you really love the Lord, your God, with all your heart and with all your soul.
5You shall follow the Lord, your God, fear Him, keep His commandments, heed His voice, worship Him, and cleave to Him.
6And that prophet, or that dreamer of a dream shall be put to death; because he spoke falsehood about the Lord, your God Who brought you out of the land of Egypt, and Who redeemed you from the house of bondage, to lead you astray from the way in which the Lord, your God, commanded you to go; so shall you clear away the evil from your midst.
- Deuteronomy 13, Torah
Deuteronomy - Chapter 13 Parshah Re eh - Tanakh Online - Torah - Bible
"God communicated to people through prophecy for nearly the entire biblical period, from Adam until Malachi. According to a prevalent Jewish tradition, prophecy ceased with Malachi, not to be renewed until the messianic age. In this article, we will consider a few traditional explanations of why prophecy ceased and some spiritual implications for Judaism over the ensuing 2,500 years and counting."
The End of Prophecy Malachi s Position in the Spiritual Development of Israel Institute for Jewish Ideas and Ideals
"There are few details recorded about the Prophet Malachi.
We do know that he was a part of the Anshei Knesset Hagedolah, the Great Assembly that met in the Holy Temple in Jerusalem at the beginning of the Second Temple era.
A panel of 120 prophets and sages--including Ezra, Nehemiah, Mordecai, Daniel, Simeon the Righteous and the prophets Haggai, Zechariah, and Malachi--which constituted the ultimate religious authority at the onset of the Second Temple Era (4th century BCE). Among their accomplishments was the composition of the text of our standard prayers and blessings."
Who Was the Prophet Malachi - Questions Answers