Hey @Djungbluth 

There could be various reasons as to why your Popup form is having trouble loading.

a culprit could be conflicting CSS interfering with your form. I’d investigate your website’s backend to see if you see any of this code in site, remove it and the issue should be resolved! 

If this isn’t the issue then I would also look into these scenarios:

• Since Klaviyo elements are designed to be loaded last and if there are many other elements on the page, you could discuss a way to optimize the elements with your site developer team
• At times, it could also be different browsers/devices which might not be display expected behavior, hence we suggest testing on different browsers/devices. 
• Lastly, we have a Klaviyo tech guide on how to improve the form performance which might also be helpful

I hope this helps,
Cheers,
Arpit

Couldn’t have said it better @ArpitBanjara.