Hi @Alexia, welcome to the community!

A few troubleshooting ideas if you are seeing someone complete a Signup Form, but not show up in your List or in Klaviyo Profiles:

• Is your Lists configured for double opt-in?  If so, even if someone submitted the form, they still have to confirm via email to get subscribed to the List.  You can learn more about this here to decide if you want to double optin or single optin: Understanding the double opt-in process
• Are the emails already Subscribed to the List?  Sometimes users may signup to a Signup Form but they are already on the List - so it may show the additional signups but not match the number of subscribers you may be expecting.
• Is the Signup Form submitting to the List you are expecting it to?  Double check the Submit Button to see which List is selected for the email submission. It just so happen that I often see this issue with SMS phone number and Email form in the same form, and it’s directed to an SMS specific List (with the email).  If you have it setup this way, consider multi-step forms so that the email can go to one List, and the SMS opt-in can go to another. 

Hope that helps you trouble shoot and let us know if they worked (or not).

Hi  @retention , 

Thank you very much for your answer. Unfortunately, I checked all the points you told me and everything seems to be correct. 

1. My list is configured for single opt-in. So my contact should appear in the list after submitting their email address.

2. I checked all my lists and the email address does not appear anywhere. So it is not already registered elsewhere.

3. I rechecked the submit button and the correct list is selected.

So in all 3 cases, everything is correct. I really don't understand where is the problem.

That really strange, @Alexia! In this case, I’d suggest reaching out to Support to take a closer look. Something funky is going on. Keep us updated with what you find out!