looping twice as much - writing doubles to MySQL table

Question

In a nutshell, my code seems to be looping twice as much as it should (writing four rows when it should be writing two rows). This should be an easy solution but I'm not having any luck.

Here is my php loop . . . must be one very simple yet invisible thing that no one has yet been able to locate why this baby is not working:

                //query statement before the for loop
                $stmt="INSERT INTO o70vm_invoices_invoices 
                (`id`, `created_by`, `user_id`, `added`, `to_name`, `to_address`, `invoice_num`, `real_invoice_num`, `from_name`, `from_address`, `from_num`, `invoice_date`, `publish`, `notes`, `template_id`, `taxes`, `start_publish`, `end_publish`, `currency_before`, `currency_after`, `status`, `to_email`, `to_company`, `from_phone`, `from_url`, `from_email`, `discount`, `invoice_duedate`, `admin_notes`, `to_city`, `to_state`, `to_country`, `to_vatid`, `to_zipcode`, `rec_year`, `rec_month`, `rec_day`, `rec_nextdate`, `is_recurrent`) VALUES ";

                // loop through number of invoices user selected to create
                for($x = 0; $x < $invoiceCount; $x++) 
                        {

                            // add the user identified days to each invoice
                            $date->modify("+7 days");
                            $invoiceDateNew = $date->format ('Y-m-d 00:00:00');
                            $invoiceDueDateNew = $date->format ('Y-m-d H:m:s');
                            $startPubNew = $date->format ('Y-m-d 00:00:00');

                            // getting the values per row
                            $ValuesAddToQuery[] ="(NULL, '792', '$userID', '$todayDate', '$parentName', 'unknown address', '0000', '0000', '', '', '', '".$invoiceDateNew."', '1', '', '2', '', '".$startPubNew."', '0000-00-00 00:00:00', '$', '', '', '$email', '$childName', '', '', '', '0.00', '".$invoiceDueDateNew."', '', '', '', '', '', '', '0', '0', '0', '0000-00-00', '0')";

                            }

                            $stmt .= implode(',',$ValuesAddToQuery);

                            mysql_query($stmt) or exit(mysql_error());

I store the number of invoices as:

    $invoiceCount  

I have echoed out the value of $invoiceCount and the value is always the same value as the user inputs. IE, user selects 2 invoices to create, displays 2 invoices in the variable, yet creates 4 invoices in the MySQL table.

Stranger more: When I check for the rows affected with:

 mysql_affected_rows()

It returns the user-selected number of invoices / rows (not the actual rows I can see are added in the MySQL Table). For example, it will say "2" rows have been affected when four rows have been added.

Even more wild . . . when I echo out the MySQL query:

   echo $stmt;

my query also shows just two rows have been added when the user selected two rows to add but the code wrote 4 actual rows.

Adventurous, I even tried to slice the array to see if I could alter the code that is sent:

                                //implode the values into the statement
                            $stmt .= implode(',',$ValuesAddToQuery);

                            //limit the length of the array
                            array_slice($ValuesAddToQuery,0,2);

                            mysql_query($stmt) or exit(mysql_error());

And, you guessed it, it changes absolutely nothing. I put the array_slice on top of the implode statement. Again, no change in the 4 rows inputted when I only want 2 rows.

The more I look at this, I can't tell in this code why it is doubling.

Any help, much appreciated.

For detailed explanation of some of my input fields and what I'm doing, follow below:

To start, I am letting the user select how many rows to copy and update the invoice date as required. I am getting the values of FREQUENCY (7 days, 14 days, or 30 days) of recurring invoices and the DURATION (number of invoices to create/copy) using these input fields:

                <select name="freqOfInvoices">
                    <option value="7">Weekly</option>
                    <option value="14">Bi-Weekly</option>
                    <option value="30">Monthly</option>
                </select>

    <input type="number" title="numberOfInvoices" name="numberOfInvoices" size="2" id="numberOfInvoices" value="numberOfInvoices" />

I have similar input fields for the three dates I'm looking to ADD x number of days to:

        // assigning variables  
        $freqOfInvoices = htmlentities($_POST['freqOfInvoices'], ENT_QUOTES);
        $numberOfInvoices = htmlentities($_POST['numberOfInvoices'], ENT_QUOTES);
        $invoiceDate = htmlentities($_POST['invoice_date'], ENT_QUOTES);
        $invoiceDueDate = htmlentities($_POST['invoice_duedate'], ENT_QUOTES);
        $startPub = htmlentities($_POST['start_publish'], ENT_QUOTES);


        //assigning number of invoices
        $countInvoices=$numberOfInvoices;

Answer 1

It seems you may only need 1 loop to construct the values.

//query statement before the foreach loop
$stmt="INSERT INTO o70vm_invoices_invoices (`id`, `.....`, etc) VALUES ";

$ValuesAddToQuery = [];

for($x = 0; $x < $arrayLength; $x++) {
    // add the user identified days to the date
    $date->modify("+7 days");
    $invoiceDateNew = $date->format ('Y-m-d 00:00:00');

    $ValuesAddToQuery[]="(NULL, '....', ".$invoiceDateNew.")";
}

$stmt .= implode(',',$ValuesAddToQuery);

mysql_query($stmt) or exit(mysql_error());