Hardhat – Error ‘namedAccounts’ Does Not Exist in Type ‘HardhatUserConfig’

Unable to add 'namedAccounts' to 'HardhatUserConfig' in hardhat.config.ts as it throws below compilation error.

'namedAccounts' does not exist in type 'HardhatUserConfig'

Below is my config file :

import "@nomiclabs/hardhat-etherscan";
import "hardhat-gas-reporter";
import * as dotenv from 'dotenv';
import { HardhatUserConfig } from "hardhat/config"
dotenv.config();

const RINKEBY_RPC_URL = process.env.RINKEBY_RPC_URL || "";
const PRIVATE_KEY = process.env.PRIVATE_KEY || "";
const ETHERSCAN_APIKEY = process.env.ETHERSCAN_APIKEY;
const GOERLI_RPC_URL = process.env.GOERLI_RPC_URL || "";

const config: HardhatUserConfig = {
  solidity: "0.8.7",
  defaultNetwork: "hardhat",
  networks: {
    rinkeby: {      
      url: RINKEBY_RPC_URL,
      accounts: [PRIVATE_KEY],
      chainId: 4
    },     
    goerli: {
      url: GOERLI_RPC_URL,
      accounts: [PRIVATE_KEY],
      chainId: 5
    },
    localhost: {
      url: 'http://127.0.0.1:8545/',
      chainId: 31337      
    },   
  },
  etherscan: {
    apiKey: ETHERSCAN_APIKEY
  },
  gasReporter: {
    enabled: true,
    outputFile: "gas-report.txt",
    noColors: true    
  },
  //This throws error
  namedAccounts: {
    deployer: {
      default: 0
    },
    player: {
      default: 1
    }
  },
}

export default config;

These are the package version's I'm using.

{
  "name": "sample-project",
  "devDependencies": {
    "@nomiclabs/hardhat-ethers": "npm:hardhat-deploy-ethers@^0.3.0-beta.13",
    "@nomiclabs/hardhat-etherscan": "^3.1.0",
    "@typechain/ethers-v5": "^10.1.0",
    "@typechain/hardhat": "^6.1.2",
    "@types/chai": "^4.3.3",
    "@types/node": "^18.7.15",
    "chai": "^4.3.6",
    "dotenv": "^16.0.2",
    "ethereum-waffle": "^3.4.4",
    "ethers": "^5.7.0",
    "hardhat": "^2.11.0",
    "hardhat-contract-sizer": "^2.6.1",
    "hardhat-deploy": "^0.11.13",
    "hardhat-gas-reporter": "^1.0.9",
    "prettier": "^2.7.1",
    "prettier-plugin-solidity": "^1.0.0-beta.24",
    "solhint": "^3.3.7",
    "solidity-coverage": "^0.8.0",
    "ts-node": "^10.9.1",
    "typechain": "^8.1.0",
    "typescript": "^4.8.2"
  },
  "dependencies": {
    "@chainlink/contracts": "^0.4.1"
  }
}