Rambam’s commentary on the Mishnah,
tractate Sanhedrin, chapter 10 says:
“When the Mashiach dies, his son will rule after him,
and his grandson will rule after that.”
CONCLUSION:
The Melech HaMashiach cannot be a childless man,
because he must have a son and a grandson who rule after him.
Rambam does not mention Mashiach returning to life, after he dies.
At its annual convention in June 1996,
the Rabbinical Council of America (RCA) declared that:
“there is not, and never has been, a place in Judaism for the belief that the Messiah, a son of David, will begin a Messianic career only to experience death, burial, and resurrection before completing it.”