Bug: Upsert with @@unique should never fail

[Untel]

Bug description

Hi !

I have this error
Unique constraint failed on the fields: (`challengeId`,`userId`)
When using a unique contraint in the where of upsert
By logic, this error should never happen as it's an upsert, it should trigger the update condition, and never add a new row.

Am i missing something ?

How to reproduce

Copy/Past the prisma information in a new project

Expected behavior

No response

Prisma information

model Participation {
  id                String @id @default(cuid())
  challengeId       String
  userId            String
  challenge         Challenge @relation(fields: [challengeId], references: [id])
  user              User @relation(fields: [userId], references: [id])
  createdAt         DateTime @default(now())
  // other stuff
  @@unique([challengeId, userId])
}

prisma.participation.upsert({
  where: {
    challengeId_userId: {
      challengeId: challengeId,
      userId: userId,
    },
  },
  update: {
    // do stuff
  },
  create: {
    user: {
      connect: {
        id: userId,
      },
    },
    challenge: {
      connect: {
        id: challengeId,
      },
    },
    // do stuff
  },
});

Environment & setup

• OS: macOS
• Database: PostgreSQL
• Node.js version: 19.9

Prisma Version

4.10.0

I also tried with 4.5.0-dev.38 following this thread

[Untel]

Well nevermind, it was an asynchronous problem.
I was doing many request in parallel.

[sxppyyy]

Well nevermind, it was an asynchronous problem. I was doing many request in parallel.

How do u fixed that error (Unique constraint failed on the fields)?

I have the same error when I try to create about 2 users asynchronously