Unable to render Signup Form to Shopify

Hello to everybody.

I integrated succesfully my Klaviyo account and my Shopify website, checked and verified and everything look perfectly on point. I followed succesfully all the Klaviyo tutorials in order to avoid to forget some steps, but I’m not able to render my Klaviyo form on my shopify frontend. Even if I publish the signup form and embed it properly, the form is not rendered properly on the website. 

I’m retrieving this error in the  console log: Failed to load resource: the server responded with a status of 422 () - fast.a.klaviyo.com/onsite/api/v2/modules?company_id=[privateAPIkey]:1 

Please let me understand how to solve this issue. I don’t know what ele i can do in order to make it work properly.