Duplication of products in GMC Data sources

Topic summary

A Shopify merchant is experiencing product duplication in Google Merchant Center (GMC) after connecting the Google and YouTube app to their store. Their product count doubled from 400+ to 900+ items.

Root Cause:
The duplication appears to stem from multiple data sources feeding products simultaneously—the Content API (created by the Google and YouTube app) and Google’s automatic product discovery.

Attempted Solutions:

  • Disconnecting the Google and YouTube app
  • Deleting the Content API data source (which automatically regenerates)
  • Allowing Google to find products organically (currently at 241 of 600+ products after 2 days)

Key Issues:

  • No “Feeds” section or “Fetch Now” option visible in their GMC interface
  • No “Diagnostics” tab available
  • Content API source reappears even after deletion
  • Slow product discovery rate (only 200 products found in 2 days)

Suggested Resolution:
A community expert recommends using a dedicated feed management app like AdNabu to create a single, controlled CSV feed, avoiding conflicts between multiple data sources and automatic imports. The merchant is seeking specific step-by-step instructions for CSV feed generation and upload locations in GMC.

Summarized with AI on October 30. AI used: claude-sonnet-4-5-20250929.

We have had our products in GMC as set up by an agency we hired years ago to do so. We encountered an issue with your products recently and in an attempt to resolve this we were advised to add the Google and Youtube app into our Shopify Sales Channels and we connected our GMC account.

This then created duplicates for all our products (we had about 400+, they went up to 900+). When you look at data sources under Provided by You and primary sources it showed Content API with the products showing 900+. In an attempt to refresh this we disconnected the Google and Youtube app and deleted the Content API source and then reconnected. It started doing the same thing, importing our products and creating duplicates of our whole catalog). The only thing we could think of was that before the shipping issues in our GMC (seperate issue) the products were showing correctly with no duplicates, but the problem started when we connected the app. So in an attempt to get back to that we disconnected the app again and deleted the Content API data source again. We are now letting that data source find our products on its own. And so far it has taken 2 days for it to find 200 products, no duplication issues so far! We still have at least another 300 for it to capture. Is there anything that can speed this up or is this just how slow it is?

Hi,

It definitely is frustrating, since posting our product count is only up to 241 currently. You mentioned Products → Feeds → Fetch Now under your primary data source. I dont see anything that says Feed. I have included a screenshot of what my options are, and there are no feeds under the Supplemental sources tab either. There are no old feeds only brand new ones that self generate (the Content API and the Found by Google one) each time I have deleted the sources in the last two weeks.

As for the CSV option, please let me know how I can do that/generate one and where to add it. Will this create duplicates since Content API just pops up no matter if I delete the source or not.

Thanks!

Just a few comments - I disconnected the Google and Youtube App and removed the Content API feed. The Content API then popped back up as a primary source. So it is there, not actually removed.

1 - what are the steps to generate a Google Shopping Feed CSV from Shopify and where in GMC do I add it specifically!

2 - we will most likely not go this route since each time is has caused issues

3 - I have no Diagnostic option/tab/section that I can find. And as the screenshot shows there are no manually added feeds.

4 - Not sure if you saw my response to the previous answer but there is no Feeds section in our GMC. There is View Data Sources, which is the screenshot I shared and there is no Fetch Now option. Can you provide an screenshots of where I could find this?

Thanks!

Hi! So, first, you must understand that duplication happens when you accidentally submit multiple feeds that use different product IDs for the same products. Except for the Google and YouTube app, were you using any other app for submitting feeds? That can cause issues.

Also, as per your question, I see that you are using Content API. When using content API, you can only check if you have multiple feeds from your website Admin. Also, ensure that you are not using Google’s automatic imports, as that can also cause duplicate issues.

That’s one case why you had duplication issues. There is a minor chance that the Google and YouTube may have had some technical issues.

Also, if you have removed the app and the content API source, but want to quickly add products without duplication, then go with a data feed solution like AdNabu. It will accurately sync your Shopify products to GMC with just a few clicks. Moreover, inside the app, you can also create a CSV file of your Shopify products and use that as a data source in Merchant center.

Let me know if you need any help with setting up the app and your feed on Merchant Center.