These errors came from the search console and it has something to do with the google data structure. Try to fill in the value for the following fields:

"priceValidUntil"

"aggregateRating"

"review"
Then test it in Google data structure tool

It means that the value for the structured data mentioned are missing. Check schema.org to see what values is suppose to be there.. and while your developer is right that it does not affect your ranking directly, it does affect how google interprets your data, hence the warning. By being so, it makes it harder for Google to categorize your content thus affecting how your page is displayed in search results. In other words, your data is not google friendly, so they say.

Sounds like a pretty lazy website developer to me.

It seems this is a problem for most shopify theme.
I have searched in shopify forum how to fix. What I got just a general guideline and I do not know the code.
Thanks

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