When using Shopify you might notice that products expire, this is because products need to be submitted every 30 days.
Currently there seems to be an issue with the Content API used by the Google Shopping app within Shopify. And both parties will tell you to contact the other party to resolve, forcing you in an endless loop.
One option is to go to the specific product that is expiring in Google Merchant Center and edit something, like the title, description, etc… this will then force Shopify to post this new data to Google Merchant Center. Your products are now active for another 30 days.
Using a text delimited,