We are trying to connect to the blockchain "https://public-node.testnet.rsk.co/1.1.0" and execute contract methods "0xdCa7EF03e98e0DC2B855bE647C39ABe984fcF21B" (EthereumDIDRegistry) and "0x0BD84E81b719d8d3d8d3d8d3d8d3d8d3d8d3d8d3d8d3d8d3d3d8d3d4d3d4d3d4d2d4d2d2d4d3d4d3d2d4d3d2d3d2d2d4d2d2d4d2d4d2d2dc9c9c9c9c One time We are trying to connect to the blockchain" https://public-node.testnet.rsk.co/1.1.0 "and execute contract methods
To achieve this, we have two accounts that we create with metamask "0xDFA518ceaEd1bfe6f704E51A18d4bB0A14714cd2" and "0x688Fb7909536C1Cd3c4977726592580EaA48ACE3" and we pass them RBTC from "https://faucek.testnet.testnet".

Running the methods from "https://remix.ethereum.org/" there seems to be no problems:

But using the same blockchain, contracts, accounts, etc. from the app I still skip the same error:

This error occurs only in the methods that modify the contract, in this case, "addDelegate" throws the error, but "validDelegate" works correctly, which sounds like a problem with the signatures.

We try to make the same call in several different ways, but we always end up with the same error. Could you give us what we are doing wrong, or at least give us a simple example where what we set out to do (interact with the contract already deployed from an api node)?

@jonathansmirnoff
We have tried in three different ways.
The first:

code
const { delegateTypes } = require("ethr-did-resolver");
const DidRegistryContract = require("ethr-did-registry");
const Tx = require("ethereumjs-tx");

var Web3 = require("web3");
const provider = new Web3.providers.HttpProvider("https://public-node.testnet.rsk.co/1.1.0");
const web3 = new Web3(provider);
const contract = web3.eth.contract(DidRegistryContract.abi).at("0x2998c93Eb2e8eA605Bf1D80065eA16B451E1678B");

module.exports.addDelegate = async function() {
web3.eth.defaultAccount = "0xDFA518ceaEd1bfe6f704E51A18d4bB0A14714cd2";

const bytecode = await contract
    .addDelegate(
                    "0xDFA518ceaEd1bfe6f704E51A18d4bB0A14714cd2",
                     delegateTypes.Secp256k1SignatureAuthentication2018, 
                     "0x688Fb7909536C1Cd3c4977726592580EaA48ACE3", 
                     9999999
                 )
    .encodeABI();

const gasPrice = web3.eth.gasPrice;
const tra = {
    gasPrice: web3.toHex(gasPrice),
    gasLimit: web3.toHex(3000000),
    data: bytecode,
    from: "0xDFA518ceaEd1bfe6f704E51A18d4bB0A14714cd2"
};

const tx = new Tx(tra);
tx.sign(new Buffer( #privateKey, "hex"));
const stx = tx.serialize();

const result = await web3.eth.sendRawTransaction("0x" + stx.toString("hex"));
console.log(result);
return result;

};
```

The second:

Third: