Upgradeable Missing Mainnet Manifest

Hello,

I successfully deployed and verified a contract on Binance Smart Chain using openzeppelin + hardhat but for some reason the manifest json file for the deployments to either testnet or mainnet network was created as unknown-XX.json where XX is the chain id from the hardhat.config.js file (i.e. unknown-56.json).

I did try to redeploy on testnet and the unknown file was the one being updated.

Any idea what could cause that?

:1234: Code to reproduce

hardhat.config.js

  networks: {
    localhost: {
      url: "http://127.0.0.1:8545"
    },
    hardhat: {
    },
    testnet: {
      url: "https://data-seed-prebsc-1-s1.binance.org:8545",
      chainId: 97,
      gasPrice: 20000000000,
      accounts: {mnemonic: mnemonic}
    },
    mainnet: {
      url: "https://bsc-dataseed.binance.org/",
      chainId: 56,
      gasPrice: 20000000000,
      accounts: {mnemonic: mnemonic}
    }
  },

package.json

  "devDependencies": {
    "@nomiclabs/hardhat-ethers": "^2.0.2",
    "@nomiclabs/hardhat-etherscan": "^2.1.7",
    "@nomiclabs/hardhat-waffle": "^2.0.1",
    "@openzeppelin/contracts-upgradeable": "^4.3.3",
    "@openzeppelin/hardhat-upgrades": "^1.12.0",
    "@openzeppelin/test-helpers": "^0.5.15",
    "chai": "^4.3.4",
    "chai-bn": "^0.3.0",
    "ethereum-waffle": "^3.4.0",
    "ethers": "^5.5.1",
    "hardhat": "^2.6.8",
    "hardhat-gas-reporter": "^1.0.4",
    "mocha": "^9.1.3",
    "web3": "^1.6.1"
  },

deploy.js

async function main() {

    const [deployer] = await ethers.getSigners();
    console.log("Deploying contract using account:", deployer.address);
    console.log("Account balance:", (await deployer.getBalance()).toString());
    const Metaframe = await ethers.getContractFactory("Metaframe");
    const metaframe = await upgrades.deployProxy(Metaframe, { initializer: 'initialize' });
    console.log("Metaframe deployed to:", metaframe.address);
}

main()
    .then(() => process.exit(0))
    .catch(error => {
        console.error(error);
        process.exit(1);
    });

:computer: Environment

hardhat version 2.6.8
solidity 0.8.2

This is expected behavior currently. The plugin doesn't know the name of the network so it calls it "unknown".