[Plugin: Google AdSense] ads not showing up

I am posting additional information here since I cannot edit my original post.

• I have disabled Adblock Plus for my website.
• I visited my website on Firefox, Internet Explorer, and Microsoft Edge, but there was no ad displayed on top of any page of my website on any of the browsers. I have also tried to visit my website on my phone to see if an ad was there without success.
• I have cleared the cache and cookies and visited my site again, but there was still no ad on top of any page.
• I am using the Twenty Sixteen theme.
• Although there is no ad, there is a little bit of blank space on top of every page.
• The plugins, other than Google AdSense, that are active are: Akismet, All In One SEO Pack, Google Analytics by MonsterInsights, Jetpack by WordPress.com, PayPal Donations, POWr Hit Counter, Rating-Widget: Star Review System, Twitter Widget Pro, UpdraftPlus – Backup/Restore, W3 Total Cache, Wordfence Security, WordPress 2-Step Verification, WP Maintenance Mode, and YouTube Subscriber.
• In addition to the active plugins, there are also three drop-in plugins: advanced-cache.php, db.php, and object-cache.php.

Is there a conflict with the plugin? I have installed Wordfence and now my ads do not show, just a blank space where the ad should be. Any luck figuring out the problem? I still have the same problem even when I disable the Wordfence plugin. Seems once I have it installed, ads don’t show. They were showing prior to me installing Wordfence plugin on many of my sites. Any help would be greatly appreciated.