S2Member Payment Problem

After integration of S2Member with PayPal, my Beta Testers found a they received a message “This invoice has already been paid. For more information, please contract the merchant.” from PayPal after the first Beta tester was successful.

Although I have read through many posts but have not seen a fix for this? Using separate pages loses the immediacy of the sale.

We have a pricing table on A KickIn Crowd Pro http://www.akickincrowd.com/pro/pricing

Can anyone give direction on how to fix?

POSSIBLE FIX: Okay, for those with this pricing table issue, I may have found a work around at PayPal. ( I will let you know after we Beta Test)

Part of the problem is S2Member settings is forcing us to send the same credentials to PayPal repeatedly. That includes IP address, and Invoice ID.

PayPal has a setting, which most of us rely as default, that denies multiple purchases using the same invoice ID. Therefore, I am going to try changing that setting in PayPal to accommodate this problem in S2Member.

Try this: You can change your settings on PayPal to allow multiple payments to the same invoice

FROM PAYPAL
Blocking Accidental Payments

You can choose whether to accept payments with the same Invoice ID or to block payments when the Invoice ID was already used.

When you receive payments from buyers, you can include an optional Invoice ID field to track payments; buyers will not see this ID. A buyer’s Invoice ID must be unique for each transaction. If PayPal receives a payment with an Invoice ID that was used for another payment, PayPal will not accept the transaction.

To set the options for blocking this type of payment:

Log in to your PayPal account at https://www.paypal.com.

The My Account Overview page opens.

Click the Profile subtab.

The Profile Summary page opens.

In the Selling Preferences column, click the Payment Receiving Preferences link.
(now found in MY SETTINGS)

The Payment Receiving Preferences page opens.
(GETTING PAID AND MANAGING RISK)

Scroll down the page to the Block accidental payments section as shown below.

Select one of the following options:

Yes, block multiple payments per invoice ID – Do not accept more than one payment per invoice. This option prevents duplicate payments that you must refund.

No, allow multiple payments per invoice ID – Do not limit the number of payments received for an invoice. Choosing this option might result in duplicate payments that require a refund.

SELECT NO allow Multiple Payments per Invoice ID>

Scroll to the bottom of the page and click the Save button.

IT WORKS! It is a work around that problem in S2Member.

I am wondering if any technical person here can show me how to reach another possible solution I found:

Another option would be to create your invoice id with user id + a random number. This would make it unique.

See below a sample code to get unique invoice numbers.

var r = Math.floor(Math.random()*100000);
var invoice = userid + “-” + r;

Where would I find the VAR’s in S2Member to make this happen?