There are a few steps you can try to resolve this issue:
Check the store's configuration: Make sure the new locations have been added to the store's shipping and delivery settings and are set to be visible at the checkout.
Clear the cache: Clearing your store's cache can often resolve strange issues with missing data. You can usually clear your cache through your store's back-end or use a caching plugin if you're using one.
Update the theme: If you've recently made changes to your store's theme, it's possible that the new locations are not being displayed because of a bug in the theme code. Try updating to the latest version of your theme or switching to a different theme temporarily to see if this resolves the issue.
Check for plugins: If you're using any plugins for shipping and delivery, make sure they are up-to-date and compatible with your store's version of the platform.
Contact support: If you've tried all of these steps and are still having trouble, consider reaching out to the support team for your e-commerce platform for further assistance.
If you could share some more details about your e-commerce platform, I might be able to provide more specific suggestions.