Starting January 17, 2022, you can no longer target countries that are not enabled in Google Merchant Center.
A merchant in Google Ads could set up dynamic remarketing campaigns for different countries simply by changing the Google Ads campaign settings. With the new requirements, Google Merchant Center country targeting is now taken into consideration.
Google now forces you to first enable display ads in Google Merchant Center for all target countries.
What Do I Need To Do?
If you target different countries in Google Ads, make sure you have enabled them in Google Merchant Center by adding the country target and shipping settings.
You can add shipping settings by going to the gear icon (top right) > shipping and returns
You can enable additional countries by submitting a new feed or using the additional countries option.