Klaviyo add to list error - Error parsing response. We got: !DOCTYPE html

  • 11 November 2021
  • 9 replies

hi guys,


Im trying to submit a new subscriber a list in klaviyo based upon the outcome of a quiz. 

We have 3 outcomes of the quiz which matches to 3 lists within Klaviyo.

All I am capturing / zapping from the form is the users first name, email address & outcome of the quiz.

I have mapping the fields and when zapier asks for which list I match it against the outcome tag that is a dropdown option in zapier. 

The outcome tag I have set to the list ID in klaviyo & i have also tried setting the outcome tag to the list name ‘I.e fitness newsletter’

I have removed double opt in for now for simplicity as well.

Keep getting the same error returned being the !DOCTYPE html error. 

Any thoughts or help would be massively appreciated!!

Ive attached a screenshot of the error as well.

Thanks so much!




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9 replies

Userlevel 7
Badge +12

Hi @benyoung01 

It looks like you are getting a parsing error, meaning something is not in the correct syntax/format. Can I get you to post some screenshots of your zap setup, so I can get a better understand of what is going wrong?


That would be great thank you!

Your’ll see on the last slide - i’ve assigned the ‘outcome tag’ in quiz builder as the ‘list Id’ for klavyio - therefore in my mind the logic is → the outcome is returned which give the klaviyo list ID → Zapier then sends that to klaviyo under the “list’ selector… Not sure if Im thinking about it correctly! Or maybe if klaviyo needs the list id & the list name or something for a user to be added? Not sure whats required by the API

Thanks so much for your help!




Userlevel 7
Badge +14

Hi @benyoung01 

Issue is likely with the List field.

Most apps when mapping dynamic variables expect the internal ID value.

You can see the expected value for the Lists by looking at the standardized list of dropdown option and notice the smaller gray value underneath the friendly value.


Hi mate,

thank you for the response - yes its the internal ID that I have tried to be returned. As I made them the outcome tag of the quiz & then called the outcome tag against the subscribe list. But it doesnt seem to work?

hi @Troy Tessalone 

thank you very much for the response! - yes its the internal ID that I have tried to be returned. As I made them the outcome tag of the quiz & then called the outcome tag against the subscribe list. But it doesnt seem to work?

Hi @GetUWired - did you get my reply please mate?

Thanks very much!


Userlevel 7
Badge +14


If you are trying to test manually, from your screenshot the value of the trigger step is “outcome tag”, which is not an expected List ID, hence the likely reason for the error.

Example, of the expected List IDs.

Notice the cryptic internal IDs underneath each friendly name, that’s what needs to be passed in dynamically via the mapped variable.


Yes you are correct thats the list ID → thats what Ive set the outcome tag as in the quiz.

Then the outcome tag 



So in my mind - under the list option where ive mapped ‘outcome tag’ - that will simply return that list ID (because thats what Ive made the ‘outcome tag’ in the quiz builder) which we need? Is that correct or am I still missing something?

Userlevel 7
Badge +14


Things to troubleshoot…

Try turning the Zap ON and testing live, then check the Zap Runs to see the DATA IN/OUT for each step to determine if the correct LIST ID is being sent on the webhook from the form to the Zap.

Otherwise, the issue is with some configuration with how the outcome tag is being sent on the webhook from the form/quiz app.

Once you figure that out, the Zap appears to be configured correctly.

Also, here’s a help article for how to change the Zap trigger test data to use to configure your Zap: