I'm not sure what the exact cause of this issue is, but I tried to remove the console.log from the custom block, and it works fine. I'm new to Node.js and Express, thus I can not get the exact issue.

As follows is my example, I tackled the issue with "express-validator": "^7.2.1",

.custom(async (value) => {
  const ticket = await Ticket.findOne({ _id: value })
  if (!ticket) {
    throw new Error("NOT_EXIST")
  }
  // console.lg('ticket result', ticket)
  return true
})

I know it's late, but I liked to share my experience and archive this solution for newbie learners like me.