How to call contract method and send value with it in web3Provider? - ethereum

Question

I'm using walletconnect/metamask as wallets, and web3Provider as provider for my "buy tokens" function.
I'm trying to use the populateTransaction.METHOD_NAME to make a transaction from my wallet to the contracts method (with BNB transfer).
I'm trying to transfer some BNB's to contract with calling the contracts "BuyTokensForBnb" function (Like we can do it with Remix IDE.)
But I keep running into errors :/
const purchaseTokens2 = async () => {
const HODLER = await new ethers.Contract(address, abi, web3providerState);
const tx = [{
nonce: "0x00", // ignored by MetaMask
to: HODLER.address, // Required except during contract publications. (LINK CONTRACT ADDRESS MAINNET/TESTNET)
value: "0xde0b6b3a7640000", // Only required to send ether to the recipient from the initiating external account.
data: '',
// Optional, but used for defining smart contract creation and interaction.
chainId: "0x61" // Used to prevent transaction reuse across blockchains. Auto filled by MetaMask.
}];
let resp = HODLER.populateTransaction.buyTokensForBnb(0, tx)
const signer = await web3providerState.getSigner();
console.log("Non signer", web3providerState);
console.log("Signer, ", signer);
console.log("Account:", await signer.getAddress());
let tx2 = await signer.sendTransaction(tx);
let signature = await signer.signMessage("Hello world");
console.log(tx2, signature);
}
BuyTokensForBnb function
function buyTokensForBnb() public payable {
require(msg.value > minbuy, "MINIMUM PURCHASE IS 0.01 BNB");
require(msg.value <= maxbuy, "MAX BUY IS 10 BNB");
require(getPresaleState() == 5 || getPresaleState() == 4, "PRESALE IS NOT RUNNING(COULD BE CANCELLED OR ENDED, OR FINALIZED)");
if(block.timestamp > endDate || block.timestamp < startDate) {
revert("You can't buy this token yet or Presale had already ended, tokens cannot be purchased any longer.");
} else {
if(getPresaleState() == 4) {
//WHITELISTED PRESALE
PresaleWallet storage presaleWallet = presaleWallets[msg.sender];
if(presaleWallet.whitelisted == false) {
if(block.timestamp >= whitelistedEndDate) {
presaleState = PresaleState.LIVE;
generateReceiptAndUserPurchasedTokens(msg.sender, msg.value);
} else {
revert('REFUNDED, YOUR WALLET IS NOT WHITELISTED');
}
} else {
//make purchase, update tokens.
generateReceiptAndUserPurchasedTokens(msg.sender, msg.value);
}
} else if(getPresaleState() == 5) {
generateReceiptAndUserPurchasedTokens(msg.sender, msg.value);
} else {
revert('REFUNDED, PRESALE IS NOT LIVE OR IN WHITELISTED MODE');
}
}
}