Thank you for reaching out to the Community! I'm happy to provide some assistance with this request, to ensure it gets resolved. To confirm I'm fully understanding, are you using a third-party theme?
As you're not experiencing any issues when installing a free copy of a Shopify theme into your shop, I'd encourage you to connect with the theme developers directly. They will be able to take a closer look into the issue and share steps on how you can get it resolved as quickly as possible.
For ease, I've gone ahead and shared a link to the Halothemes Support Page, where you can connect with them directly.
Please let me know if you have any other questions or concerns.
Blair | Shopify - Was my reply helpful? Click Like to let me know! - Was your question answered? Mark it as an Accepted Solution - To learn more visit the Shopify Help Center or the Shopify Blog