Hello @Mark Martin,

Thanks for sharing your question with the Klaviyo Community!

Since this pertains to a console warning/error, I would suggest reviewing your site code to see if there were any other additional codes on the website that may be impacting the Klaviyo.js preventing the signup form from rendering. In addition a 403 or 404 errors indicate that the access to those scripts has been forbidden or blocked by the requested server. This is usually the result of a permission issue which is another area I would suggest checking up on!

If you need further assistance pertaining to your site code and further diving into this error, I would recommend working with your developer or reaching out to a Klaviyo Partner who can provide a more comprehensive review of your site code.

I hope this helps!

David