DGRAPH-couldn't rewrite mutation addRefurbishmentRequest because failed to rewrite mutation payload because duplicate XID found: Others

Question

I am using DGraph: When i am updating two item with description key I am getting this error

SCHEMA:

type RefurbishmentRequest {
  id: ID!
  items: [RefurbishmentItem]
  purchase: Purchase @hasInverse(field: "refurbishment")
  issue: Issue @hasInverse(field: "refurbishment")
  requestStatus: RefurbishmentStatus
  raisedBy: User @hasInverse(field: "raisedRefurbishments")
  hasTransportationCharge: Boolean
  transportationCharge: Int
  createdAt: DateTime
  refurbishmentBeneficiary: RefurbishmentBeneficiary
  refurbishmentDetails: RefurbishmentDetails @hasInverse(field: "requests")
}

type RefurbishmentItem {
  id: ID!
  product: Product!
  quantity: Int
  price: Int
  refurbishmentProofUrl: String
  installationProofUrl: String
  expectedBuyingPrice: Int
  status: RefurbishmentStatus
  description: String
  abcDescription:String
}

type Product {
  id: ID!
  name: String! @id
  Newdescription: String
  variant: String
}

I tried to change key but it is not working error is still same:

{
  "message": "couldn't rewrite mutation addRefurbishmentRequest because   failed to rewrite mutation payload because duplicate XID found: Others",
       "path": [
        "addRefurbishmentRequest"
      ]
     }
  ],