Hi all,

I would just like to ask for assistance. I am using Klaviyo’s JS API track() to track our events. I’ve added a callback function to the track() method to be able to identify if it’s success or not by creating a log file .

if (typeof klaviyo !== 'undefined') {
            // Klaviyo.track with callback for response handling
            klaviyo.track(eventName, eventData, (response) => {
                if (response && response.success !== false) {
                    // Success - write success log to server file
                    this.writeToServerFile(eventName, {
                        ...eventData,
                        klaviyoResponse: response
                    }, 'success');
                    console.log(`✅ Klaviyo ${eventName} tracked successfully:`, response);
                } else {
                    // Failed - write error log to server file
                    const error = response ? response.error : 'Unknown error';
                    this.writeToServerFile(eventName, {
                        ...eventData,
                        klaviyoResponse: response
                    }, 'error', error);
                    console.error(`❌ Klaviyo ${eventName} tracking failed:`, error);
                }
            });
        } else {
            const error = 'Klaviyo not available';
            this.writeToServerFile(eventName, eventData, 'error', error);
            console.error(`❌ ${error} for ${eventName}`);
        }

On top of that right before we receive a response from track(), we are creating a log file already. Therefore, I assume that for every event triggered atleast 2 files should be created:

• Attempt log file (always created whenever we trigger the event on the website (e.g. via button click)
• Either a success or an error log file depending on the callback response of the track() API.

However, what happens was I only able to create attempt log files. Do you have any idea why it’s failing or why I can’t receive the callback response from the track() method? Are there blockers you encountered previously?

Thank you.