If you configure anything in your backend then you have to wait some time as per the default cache lifetime. If you need to see it immediately after configuring some settings, then clear the browser cache or check-in the incognito mode.
Clear Cache
To clear cache go to System ➤ Tools ➤ Cache Management, you will land on the “Cache Management” page.
Press the “Flush Magento Cache” to clear the cache. It is recommended to always refresh the browser to make sure you can find the most recent file. After this, you may need to clear the browser cache to see the updated content.