PayPal "This invoice has already been paid"

Hello! I am getting this strange error for some reason. It is only happening in the browser on my phone, and not in Firefox or Chrome on my computer. But if it’s happening for anyone that is the potential of sales being lost!

I searched around previous threads and saw you suggested to share the paypal logs. They were already enabled and I have the log files that I can send you (let me know how), so you can see if there is something in my button code causing this.

It’s happening for some buttons but NOT others. So the main landing page leads to the paypal error “This invoice has already been paid”, but then clicking the buttons on the FAQ page (same browser etc.) and it works fine and it’s ready to process the payment.

I looked at the button code for the pages it is happening on and compared it to the pages that when the buttons were clicked I was successfully sent to paypal, and they are precisely the same, character for character.

Please help me figure this out. Thanks!

Any chance you can you provide us links to the pages so we can test?

I’m currently running A/B tests on the pages, but here are links to the two versions (different button codes used in each):

Version A
Version B

Version A on the main page is the one giving me problems on my Android system, but when I click to the “Frequently asked questions” page and try to buy there, I get through fine.

• This reply was modified 4 years, 4 months ago by  Benny Lewis.

Hi Benny,

You said,

I looked at the button code for the pages it is happening on and compared it to the pages that when the buttons were clicked I was successfully sent to paypal, and they are precisely the same, character for character.

I just looked at the code for the buttons on the two pages and they are not the same. Please copy/paste the working button code from the working page to the non-working page and test again.

Are you comparing split test A and the /faq/ page? There is also a /frequently-asked-questions/ page that is pertinent to split test B.

In both the main page of A and /faq/, this is the code being used

[s2Member-PayPal-Button level="3" success="http://www.speakfromday1.com/thank-you/" ccaps="" desc="Speak from Day 1 + Full Language Hacking Guide package" ps="paypal" lc="" cc="USD" dg="0" ns="1" custom="speakfromday1.com" ta="0" tp="0" tt="D" ra="97" rp="1" rt="L" rr="BN" rrt="" rra="1" image="http://speakfromday1.com/wp-content/themes/OptimizePress/images/addtocart-style1.png" output="button" /]

It’s precisely the same, character for character. If you are getting different readings from them, it’s possible that my A/B split test is interfering in some way, although I don’t see how.

Hello? This problem has escalated!! Now it’s not allowing sales to go through AT ALL on one iteration of my page :(
This link http://speakfromday1.com/?_vis_test_id=3&_vis_opt_random=0.6976607865326538&_vis_opt_preview_combination=2 represents funnel A of my A/B test, and this link:
http://speakfromday1.com/?_vis_test_id=3&_vis_opt_random=0.008910088907053026&_vis_opt_preview_combination=3
Represents funnel B. ONLY BUTTONS ON THE SECOND LINK ARE WORKING. On the first link I get the paypal error!

This has been happening over the last 12 hours, and because of this I’ve lost several hundreds of dollars of sales. There is only one difference between the buttons on both pages (whether the price is 87 or 97), and that’s the success thank you page. Nothing else.

Previously, this was a minor annoyance, as it was just happening on mobile browsers. Now I see it on all my browsers and confirm no sales are coming through. Please help me fix this!

• This reply was modified 4 years, 4 months ago by  Benny Lewis.

OK, I think I might have found the problem. It’s annoying how much time I wasted to get here, but hopefully this will help someone else in future.

Using VWO on a traditional A/B test, where a single page has particular points altered (as you may have seen me discuss in a different thread), means that the page is actually run OFF SERVER. I wasn’t aware of this, but clearly that messed up the use of s2member and its buttons (as well as my affiliate tracking system).

So, using the same system, I’ve created a SPLIT TEST. This is subtely different in that it automatically redirects people to two URLs on my site, and as such everything is displayed on my server and now the buttons are working fine.

Since all it does is randomly split to two URLs rather than dynamically change content on arrival, I’m starting to think that this plugin was a huge waste of time, since I can get conversion data on Google Analytics and have a simpler plugin split traffic randomly. For future reference, this is my recommendation to avoid VWO with s2member!

As a closing question, can anyone recommend a WordPress plugin that randomly splits between 2 URLs? This is all anyone else will ever need if they would like to do split testing on their sales pages. Then you would set up 2 thank you pages that each alternative URL sends to, and track these as goals in Google Analytics. Sure beats paying several hundred dollars a month for the service…

Any good plugin recommendations? Or simple split test systems I can use as an alternative? Don’t mind paying for it if it is a once off!

Hi Benny,

Thank you very much for sharing all this information. I’m sure it will help others who are after a similar solution.

I don’t know of any WordPress plugins that randomly split the redirects, but have you tried searching Google for “wordpress split test plugin“?