Hello Brevo Community,
I am currently facing one persistent issue with my website’s Brevo integration, and I am hoping someone can help me understand what might be causing it. The specific problem is that contact form submissions made through my website are not consistently appearing in Brevo, even though the form itself appears to submit successfully to the visitor. When a user fills in the form and clicks the submit button, the website displays the expected confirmation message, so from the user’s perspective the submission appears to have completed normally. However, some of those submissions do not subsequently appear in the expected Brevo contact list. The issue is intermittent rather than affecting every submission, which makes it difficult to determine whether the website is failing to send certain requests, Brevo is receiving but not processing them, or the integration is losing the submission somewhere between the website and Brevo.
I have verified that the Brevo integration is correctly configured on the website and that the form is connected to the intended contact list. Normal test submissions sometimes appear in Brevo almost immediately, which confirms that the basic integration is functioning. The problem occurs when I submit the form repeatedly using different test addresses and, occasionally, one submission will successfully create the contact while another submission using the same form structure will not appear as expected. The website does not display an error to the visitor when this happens because the form considers the submission successful. I have checked the form fields and confirmed that the information being collected corresponds to the fields configured in Brevo. Because the exact same form can successfully send some contacts while apparently missing others, I am trying to identify what distinguishes the affected submissions from the successful ones.
I have also inspected the browser’s developer tools and network activity while submitting the form to determine whether the request is actually being generated. The submission request appears to be made normally, and there is no obvious frontend JavaScript exception at the time the visitor submits the form. The website’s backend also continues functioning normally, so this does not appear to be a general website outage. I have compared the timestamps of successful submissions with the timestamps of missing submissions and am trying to correlate them with the corresponding requests in my website logs. In the successful cases, I can trace the form submission through the expected workflow, while in the affected cases I do not yet have enough information to determine whether Brevo received the request and rejected it or whether the request never reached Brevo in the first place.
The problem becomes particularly important because the website relies on these form submissions to maintain an accurate list of contacts. If a visitor receives a successful confirmation message but their contact is not added to Brevo, I have no reliable way of knowing from the website interface that anything went wrong. I have checked the contact list manually after test submissions and have found that the expected contact can sometimes be missing even though the form showed a successful submission. I have also tried submitting the same details again, and in some cases the second attempt is processed correctly, but I do not want to rely on duplicate submissions as a workaround because real visitors should not have to submit the same form multiple times. I am therefore trying to determine whether there is a recommended way to verify the final delivery and processing status of each submission.
I have reviewed the integration configuration and have not intentionally changed the form or Brevo settings immediately before the issue occurs. I am also trying to determine whether contact attributes, duplicate email addresses, subscription status, consent handling, or another Brevo-side validation process could cause a submission to be accepted by the website while preventing the expected contact from appearing in the list. I do not want to assume that a missing contact necessarily means the API request failed, because the request could potentially be accepted and processed differently depending on the submitted data. I have started recording submission timestamps and non-sensitive identifiers so that I can compare an affected submission with one that successfully appears in Brevo. My main goal at this stage is to find a reliable method of tracing one specific form submission from the website all the way through to its final state inside Brevo.
I would appreciate guidance from the Brevo community on how to properly troubleshoot this intermittent contact-submission problem. Specifically, I would like to know how I can verify whether an individual website submission actually reached Brevo, whether there are logs or event information that can show why a contact was not created or updated, and which API or integration responses I should capture during the submission process. I would also appreciate advice on the best way to distinguish between a website-side delivery failure and a Brevo-side processing or validation issue. My goal is to make the integration reliable so that whenever a visitor receives a successful form submission confirmation, the corresponding contact is consistently processed by Brevo without requiring duplicate submissions or manual checking of the contact list. Sorry for long post!