If you receive a message regarding the disapproval of a Merchant Center account, this is because someone made a change in the Comparison Shopping Services (CSS) dashboard for that account. As a result, the CSS can no longer show products for this account. To fix this, follow the instructions below.
If you're a merchant:
In your Merchant Center account, click Settings
in the left hand navigation menu.
Select General and go to Comparison Shopping Services tab.
Select Shopping ads setup.
Expand the “CSSs” panel under "Comparison Shopping Services (European Economic Area, the United Kingdom, and Switzerland)".
In the "Enabled" column, check the box next to the CSS you'd like to enable.
Click Save.
If you're a Comparison Shopping Service:
Reach out to the merchant who has opted out of allowing you to advertise their products on Google. They'll need to go into their Merchant Center account and re-enable your service.