Google ads can not detect the conversions that come from google shopping?

I really got headche, I use shopify to build my site and recently shopify upgarded their checkout page ( I used to mannually set google conversion code to thank you page ), so that I have to use their Google & Youtube app for tracking google ads conversion. But weird thing is that Google Ads detected conversions, but they weren't attributed to Google Shopping. Therefore, they can't be logged under the Shopping campaigns or used to optimize bidding. What's the issue?

You can check whether the conversions appear at the account level but aren’t attributed to shopping and verify the campaign’s conversion goals and the app’s purchase-event mapping before reinstalling anything.