Transaction.callContract using 1559 and .signTransaction fails

[danielnordh]

I'm creating a signed transaction on a mobile client which is then passed to a node server for submission. This works when not including 1559 gas parameters:

final transaction = Web3Dart.Transaction.callContract(
        contract: usdcContract,
        function: usdcContract.function('transferWithAuthorization'),
        parameters: [
          Web3Dart.EthereumAddress.fromHex(user.pubKey!),
          toAddress,
          amount,
          BigInt.from(validAfter),
          BigInt.from(validBefore),
          nonce.bytes,
          BigInt.from(sigParams.v),
          bigIntToUint8List(sigParams.r),
          bigIntToUint8List(sigParams.s),
        ]
);
final signedTx = await ethClient.signTransaction(
    wallet.privateKey, 
    transaction,
    chainId: config.chain.chainId, 
    fetchChainIdFromNetworkId: false);
hexTx = "0x" + hex.encode(signedTx);

But when adding the 1559 parameters maxFeePerGas and maxPriorityFeePerGas, it fails when submitting on the node server with the following error: transaction could not be decoded: could not decode RLP components: could not decode list item 3 to Address: invalid address: 0x22ecb25c00

final transaction = Web3Dart.Transaction.callContract(
        contract: usdcContract,
        function: usdcContract.function('transferWithAuthorization'),
        parameters: [
          Web3Dart.EthereumAddress.fromHex(user.pubKey!),
          toAddress,
          amount,
          BigInt.from(validAfter),
          BigInt.from(validBefore),
          nonce.bytes,
          BigInt.from(sigParams.v),
          bigIntToUint8List(sigParams.r),
          bigIntToUint8List(sigParams.s),
        ],
        maxFeePerGas: Web3Dart.EtherAmount.fromUnitAndValue(Web3Dart.EtherUnit.gwei, 150),
        maxPriorityFeePerGas: Web3Dart.EtherAmount.fromUnitAndValue(Web3Dart.EtherUnit.gwei, 3),
);
final signedTx = await ethClient.signTransaction(
    wallet.privateKey, 
    transaction,
    chainId: config.chain.chainId, 
    fetchChainIdFromNetworkId: false);
hexTx = "0x" + hex.encode(signedTx);

I'm using web3.js 1.7.1 on the node server and the js snippet for submitting the transaction is:

Web3.eth.sendSignedTransaction(hexTx, function (err, hash) {
    if (!err) {
      response.end(JSON.stringify({"hash": hash }));
    } else {
      response.end("Error!");
    }
  });

If I use .sendTransaction (instead of .signTransaction) on the mobile client using the 1559 parameters it works. Is there something I'm missing in the combo of .callContract and .signTransaction when using 1559, or is something broken?

[kaumudpa]

I am facing the same problem.