How to fix common unique identifiers error in Google Merchant Center (Limited performance due to missing identifiers [gtin, mpn, brand])
If you’re getting this error in Google Merchant Center, it means that one or more of your product listings are missing unique product identifiers (UPIs). These identifiers— GTIN, MPN, and Brand—help Google properly categorize and rank your products in Shopping Ads. Without them, your ads may still show but with lower performance.
The good news? You can fix this issue by providing at least two of these identifiers. If your product doesn’t have a GTIN, you can submit the MPN and Brand instead.
Check with your supplier to get the correct MPN for your products.
Go to your Shopify store and navigate to Products.
Edit your product variant by clicking on the product you need to update.
Enter the MPN in the SKU box.
Save your changes, and the information will sync into FeedHub and submit to Google Merchant Center.


Confirm that your product truly has no GTIN by checking with the manufacturer.
If there is no GTIN, make sure you have both the MPN and Brand added to your product details.
Update your product feed to Google Merchant Center by ensuring the correct fields are filled.
Need Help?
If you run into any issues while fixing these errors, feel free to reach out! Drop us a message in the live chat or email us at support@socialhead.io. We’re happy to assist!
Curious to read more? Check out additional articles:
How to fix issue "Invalid sale price" on your Google feed
How to solve the disconnected issue on Google feed
The good news? You can fix this issue by providing at least two of these identifiers. If your product doesn’t have a GTIN, you can submit the MPN and Brand instead.
Situation 1: Your Products Are Missing MPN and Brand
Steps to Fix It
Check with your supplier to get the correct MPN for your products.
Go to your Shopify store and navigate to Products.
Edit your product variant by clicking on the product you need to update.
Enter the MPN in the SKU box.
Save your changes, and the information will sync into FeedHub and submit to Google Merchant Center.


Situation 2: Your Product Has No GTIN
Steps to Fix It
Confirm that your product truly has no GTIN by checking with the manufacturer.
If there is no GTIN, make sure you have both the MPN and Brand added to your product details.
Update your product feed to Google Merchant Center by ensuring the correct fields are filled.
Need Help?
If you run into any issues while fixing these errors, feel free to reach out! Drop us a message in the live chat or email us at support@socialhead.io. We’re happy to assist!
Curious to read more? Check out additional articles:
How to fix issue "Invalid sale price" on your Google feed
How to solve the disconnected issue on Google feed
Updated on: 17/03/2025
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