why are my if/else statements not outputting the equations being used, not sure what I am doing wrong?

in my introductory coding class, we are currently working on if/else statements. We do scripting within our html document, and I have provided the code I have been working on down below. I am very confused about why my information is not being outputted when I run my code. Essentially, we have to use if/else statements for if a customer purchases more than 150 clubs, and in our code we need to show an equation for if they input a number greater than 18 for cost per club. My if/else statements reflect this, and I have also checked my code for grammar mistakes but I am not finding any. Any help with this issue would be extremely appreciated! Thank you!

This part is what I have in my html:

<form id="userInformationEntry">
    <p><label for="txtPutterQuantity">How many golf clubs would you like to 
    order:</label>
        <input type="text"  id="txtPutterQuantity"  maxlength="100"  
        size="50"></p>
    <p><label for="txtPutterCost">How much is the cost to be paid per golf 
    club:</label>
        <input type="text"  id="txtPutterCost"  maxlength="100"  size="50"> 
    </p>
    <p><label>Would you like to be added to the mailing list?</label></p>
    <p><label for="radFirstChoice">Yes</label>
        <input type="radio"  id="chkYes"  name="optionChoice1" 
        checked="checked"></p>  
    <p><label for="radSecondChoice">No</label>
        <input type="radio"  id="radSecondChoice"  name="optionChoice2"></p>
    <p><input type="button"  value="Submit Order Information"  
    onclick="submitOrderFunction"></p>
    <br>
    <br>
</form>

<div id="orderInformationResults">
</div> <!--end of orderInformation div-->

This part is what I have in my script:

function submitOrderFunction()  {
    var golfClubAmount, golfClubCost;
    var deductionAmount;
    var totalAmount;
    var truePrice;
    var resultsString;

    golfClubAmount = document.getElementById("txtPutterQuantity").value;
    golfClubCost = document.getElementById("txtPutterCost").value;
    golfClubAmount = parseInt(golfClubAmount);
    //Only whole numbers would be enetered because you can't give half or a 
    quarter of a club
    golfClubCost = parseFloat(golfClubCost);
    //Decimals may be used if someone will be paying some change as well (ex: 
    $21.50)
    totalAmount = (golfClubCost - 18) * golfClubAmount;
    totalAmount = totalAmount.toFixed(2);
    totalAmount = parseFloat(totalAmount);

    //the 10% off deduction exclusively for orders of 150 clubs or more
    if (golfClubAmount > 150 )
    {
        deductionAmount = totalAmount * .90;
    }
    else
    {
        deductionAmount = 0;
    }

    truePrice = totalAmount + deductionAmount;
    truePrice = truePrice.toFixed(2);
    //We need to limit to two decimal places
    truePrice = parseFloat(truePrice);
    //We will be working with decimals, so parseFloat seems like the better 
    function to use

    resultsString = "For an order of " + golfClubAmount + " clubs, at $" + 
    golfClubCost + " per club, you will earn $" + truePrice + "."
    document.getElementById("orderInformationResults").innerHTML = 
    resultsString;
}

If anyone can lead to what I am doing wrong, I would greatly appreciate it, or if anyone has any insights, thank you!