intermittent recaptcha fail

[BobLodi]

We have Marketo forms embedded on a WordPress site. The forms have recaptcha turned on.  Lately, every so often, a form fails to submit and we get a "Submission failed, please try again later." message. When I look into it, I see a "errorCode 400, Captcha field missing in form".

We do *not* have WP Rocket or any other optimizer installed, so, there are not those settings to change that I have seen in other threads. (https://nation.marketo.com/t5/product-discussions/can-t-submit-the-form-with-recaptcha-enabled/m-p/3...)

It is very random, I can sit there and submit tests all day and not see the error pop up, then suddenly it will.

It has also been reported by customers, so, thats causing some worry with the marketing team.

This is the form - https://us.sios.com/demo-request/

I'm out of ideas - other than starting to turn things on and off on the WordPress side - but - since the error is so hard to repeat, that could take a while to get sorted out, if we can even tell. 

Any other suggestions are welcome - thanks in advance.

[SanfordWhiteman]

Are you using Known Visitor HTML?

[BobLodi]

Good question. I am not sure - but I can check.

[BobLodi]

Apparently yes we are using Known Visitor  - client sent me this:

[SanfordWhiteman]

That’s actually showing that you aren’t using KV HTML (the options are KV Custom HTML  or just showing the form).

[SanfordWhiteman]

It looks you’re using my custom ReCAPTCHA code and also have the new native Marketo ReCAPTCHA v3 turned on. You should only be using one of these!

[BobLodi]

OK, so not using the HTML. Good to know.

For the double recaptcha - this site was set up before the Marketo universal recaptcha - whatever its called - happened last fall. 

When I read about that, I made a test form here the other day - https://us.sios.com/test-test-demo-test/

its password protected (pw = captcha)

This form does *not* have the embedded captcha scripts. And we still get the same error.

[SanfordWhiteman]

The problem on that page is you have 2 Marketo forms. The native reCAPTCHA isn’t supported in that setup. My custom reCAPTCHA JS should still, however you need to move completely to the custom setup.

[BobLodi]

Oh they have the newsletter sign up too. thats a Marketo form.

So - i should turn OFF the native (new late 2022) captcha, and just use the custom... that at least sounds like something we can try.

Thank you - more as I know it.

[SanfordWhiteman]

Correct, you need to disable Marketo native reCAPTCHA as with 2 forms, you have a race condition where it will only ever work on one at a time (thus the “intermittent” perception).