Failed to deploy MACI to Kovan testnet

[johnson86tw]

Run yarn hardhat run scripts/deploy/deployMaci.ts --network kovan

Generating typings for: 0 artifacts in dir: typechain/ for target: ethers-v5
Successfully generated 3 typings!
Successfully generated 11 typings for external artifacts!
linkedLibraryAddresses:  {
  'maci-contracts/contracts/crypto/Hasher.sol:PoseidonT5': '0xa8d4452Ae282FC13521C6A4d91FE58bB49719EB4',
  'maci-contracts/contracts/crypto/Hasher.sol:PoseidonT3': '0xa9228cA5f3dFCE19a61b7Bf1540F21C9e9d95a2b',
  'maci-contracts/contracts/crypto/Hasher.sol:PoseidonT6': '0xc90d37Dc42a178D908AE97C9D53d22c6e4Eae812',
  'maci-contracts/contracts/crypto/Hasher.sol:PoseidonT4': '0x9cDD2E83ebAD5d7B0cDd75bbaD169F0D21C3fE67'
}
Deploying MACI...
ProviderError: The execution failed due to an exception.
    at HttpProvider.request (/Users/johnson/Desktop/qv-contracts/node_modules/hardhat/src/internal/core/providers/http.ts:74:19)
    at LocalAccountsProvider.request (/Users/johnson/Desktop/qv-contracts/node_modules/hardhat/src/internal/core/providers/accounts.ts:188:34)
    at processTicksAndRejections (node:internal/process/task_queues:96:5)
    at async EthersProviderWrapper.send (/Users/johnson/Desktop/qv-contracts/node_modules/@nomiclabs/hardhat-ethers/src/internal/ethers-provider-wrapper.ts:13:20)

But it works on Rinkeby testnet.