Go Ethereum Sending EIP155 Transaction

I am trying to send a EIP155 transaction using go but when signing i keep getting the error "transaction type not supported". I was wondering if i am doing something wrong?

tx := types.NewTx(&types.DynamicFeeTx{
    ChainID: chainID,
    GasFeeCap: maxGas,
    Nonce:    nonce,
    To:       &contractAddress,
    Value:    transactionValue,
    Gas:      gasPrice.Uint64(),
    Data:     data,
})

signedTx, err := types.SignTx(tx, types.NewEIP155Signer(chainID), privateKey)
if err != nil {
    fmt.Println("Error signing transaction: ", err)
    return
}