This mean you have 2 Klaviyo account on the same site. (I guess 2 different accounts)

There is a BUGGGGGGGGG when you open Klaviyo app from shopify with different accounts it create new account in Klaviyo for each of them.

Hi @M.Mourad, 

This error is due to multiple scripts of Klaviyo’s onsite javascript being present on your page. And as @David B., points out this can occur if you integrate subsequent Shopify stores to the same Klaviyo account. Rather than installing the Klaviyo app through the Shopify store, your best bet is to integrate with Shopify from within Klaviyo. We have a great article walking you through this step-by-step here.

In terms of fixing the problem, removing duplicates scripts of javascript can currently only be done by a Klaviyo support staff member. Therefore, you’ll need to reach out to support  to get this remedied.

Thanks and have a wonderful rest of your day!