I am trying to get the balance of any ERC20 token of my wallet via a PHP code like:

  public function getErc20TokenBalance(string $tokenAddress, callable $callback): void
{
    // ERC20 ABI definition (balanceOf function)
    $abi = '[{"constant":true,"inputs":[{"name":"_owner","type":"address"}],"name":"balanceOf","outputs":[{"name":"balance","type":"uint256"}],"type":"function"}]';

    // Encode the function call
    $data = '0x70a08231000000000000000000000000' . substr($this->fromAddress, 2); // Method ID + address without '0x'

    // Convert tokenAddress to lowercase and ensure it has '0x' prefix
    $tokenAddress = strtolower($tokenAddress);
    if (substr($tokenAddress, 0, 2) !== '0x') {
        $tokenAddress = '0x' . $tokenAddress;
    }

    // Setup transaction
    $transaction = new EthereumTx([
        'to' => $tokenAddress, // Ensure $tokenAddress is passed as string
        'data' => $data
    ]);

    // Call contract using web3 instance with callback function
    $this->web3->eth->call($transaction, function ($err, $result) use ($callback) {
        if ($err !== null) {
            throw new Exception('Error getting balance: ' . $err->getMessage());
        }

        // Parse result
        $balance = new BigNumber($result->toString());

        // Call the provided callback function with the balance
        $callback($balance->getValue());
    });
}

and I always get error: Wrong type of eth_call method argument 0. on line $this->web3->eth->call($transaction, function ($err, $result) use ($callback) {

I am using the web3 library (https://github.com/web3p). I assume maybe the transaction object is wrong, but not sure why.