Warnings are suggestions for improvement. Some warnings can affect your appearance on Search; some might be reclassified as errors in the future. The following warnings were found on your site:
Missing field "aggregateRating"
Missing field "sku"
Missing field "priceValidUntil"
Missing field "brand"
Missing field "review"
We recommend that you fix these issues when possible to enable the best experience and coverage in Google Search.
How to fix? my site is https://theproshopping.com/
I checked and seems like there are no Product meta tags setup properly in your product page. You can check that warning using this link https://search.google.com/structured-data/testing-tool#url=https%3A%2F%2Ftheproshopping.com%2Fcollec...
Please check this link https://feedarmy.com/kb/shopify-microdata-for-google-shopping/ It's JSON-LD data but you can get idea about your missing fields and value.
If you are not comfortable to fix it then just let me know, I will send request for the Admin collaborate access and will fix it from my side.
Which review app you have installed on your store?
If you tell me then I can fix it.
You need not reply properly about the app installation. Because the issue you have mentioned is related to "Product review App" and the above app list you have mentioned is not contains any review app. If it is possible to send a screenshot of admin--> apps ?
Okay, I have found an issue you have not installed any Product review on your store. Moreover, you are using meta schema for SEO that causes this issue because it is not getting review details so you need to Review App. So I have attached a few apps below that can help you to fix the issue but for that, you need to install anyone from them.
After that, if the issue is not fixed then let me know.