Using Metafields Guru App for Schema Markup

Hey everyone, I'm taking over the SEO operations of a Shopify store, and noticed Google Search Console is giving the store a number of warnings (no errors) due to invalid schema markups. These errors appear on products and collection pages.

My client would like these fixed to have the best possible standing in search. The SEO before me was using the Metafields Guru app to create the schema, and although the JSON is added in the app, Google still returns these warnings.

I'm unfamiliar with the app, so I contacted Metafields Guru support, they seem to think it is misaligned settings in Google Search Console, but I'm not so sure, as everything in GSC looks fine. 

To take this a little further, I created my own schema text, verified the code through the Rich Results Test page and it was valid, but when I replaced my 'validated' JSON with the text in the app from the previous SEO, nothing changed.

I'm wondering if anyone has had this issue and knows how to solve it? I watched a video on YouTube about editing the Liquid file for the products and copy + pasting the JSON text in manually, but I'd rather let the app handle this if possible, as there are quite a few products and collection pages there are errors on.

Thanks for any help!

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